Main:z from

Percentage Accurate: 91.8% → 98.7%
Time: 15.4s
Alternatives: 22
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (+
  (+
   (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
   (- (sqrt (+ z 1.0)) (sqrt z)))
  (- (sqrt (+ t 1.0)) (sqrt t))))
double code(double x, double y, double z, double t) {
	return (((sqrt((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(x, y, z, t)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    code = (((sqrt((x + 1.0d0)) - sqrt(x)) + (sqrt((y + 1.0d0)) - sqrt(y))) + (sqrt((z + 1.0d0)) - sqrt(z))) + (sqrt((t + 1.0d0)) - sqrt(t))
end function
public static double code(double x, double y, double z, double t) {
	return (((Math.sqrt((x + 1.0)) - Math.sqrt(x)) + (Math.sqrt((y + 1.0)) - Math.sqrt(y))) + (Math.sqrt((z + 1.0)) - Math.sqrt(z))) + (Math.sqrt((t + 1.0)) - Math.sqrt(t));
}
def code(x, y, z, t):
	return (((math.sqrt((x + 1.0)) - math.sqrt(x)) + (math.sqrt((y + 1.0)) - math.sqrt(y))) + (math.sqrt((z + 1.0)) - math.sqrt(z))) + (math.sqrt((t + 1.0)) - math.sqrt(t))
function code(x, y, z, t)
	return Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(sqrt(Float64(y + 1.0)) - sqrt(y))) + Float64(sqrt(Float64(z + 1.0)) - sqrt(z))) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)))
end
function tmp = code(x, y, z, t)
	tmp = (((sqrt((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
end
code[x_, y_, z_, t_] := N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)
\end{array}

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 22 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 91.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (+
  (+
   (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
   (- (sqrt (+ z 1.0)) (sqrt z)))
  (- (sqrt (+ t 1.0)) (sqrt t))))
double code(double x, double y, double z, double t) {
	return (((sqrt((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(x, y, z, t)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    code = (((sqrt((x + 1.0d0)) - sqrt(x)) + (sqrt((y + 1.0d0)) - sqrt(y))) + (sqrt((z + 1.0d0)) - sqrt(z))) + (sqrt((t + 1.0d0)) - sqrt(t))
end function
public static double code(double x, double y, double z, double t) {
	return (((Math.sqrt((x + 1.0)) - Math.sqrt(x)) + (Math.sqrt((y + 1.0)) - Math.sqrt(y))) + (Math.sqrt((z + 1.0)) - Math.sqrt(z))) + (Math.sqrt((t + 1.0)) - Math.sqrt(t));
}
def code(x, y, z, t):
	return (((math.sqrt((x + 1.0)) - math.sqrt(x)) + (math.sqrt((y + 1.0)) - math.sqrt(y))) + (math.sqrt((z + 1.0)) - math.sqrt(z))) + (math.sqrt((t + 1.0)) - math.sqrt(t))
function code(x, y, z, t)
	return Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(sqrt(Float64(y + 1.0)) - sqrt(y))) + Float64(sqrt(Float64(z + 1.0)) - sqrt(z))) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)))
end
function tmp = code(x, y, z, t)
	tmp = (((sqrt((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
end
code[x_, y_, z_, t_] := N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)
\end{array}

Alternative 1: 98.7% accurate, 0.3× speedup?

\[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{z + 1} - \sqrt{z}\\ t_3 := \frac{1}{t\_1 + \sqrt{y}}\\ t_4 := t\_1 - \sqrt{y}\\ t_5 := \sqrt{x + 1} - \sqrt{x}\\ t_6 := \sqrt{t + 1} - \sqrt{t}\\ t_7 := \left(\left(t\_5 + t\_4\right) + t\_2\right) + t\_6\\ \mathbf{if}\;t\_7 \leq 2 \cdot 10^{-5}:\\ \;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + t\_3\right) + t\_2\right) + t\_6\\ \mathbf{elif}\;t\_7 \leq 2.01:\\ \;\;\;\;\left(\left(t\_5 + t\_3\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + 0.5 \cdot \frac{1}{\sqrt{t}}\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_4\right) + t\_2\right) + t\_6\\ \end{array} \end{array} \]
NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
(FPCore (x y z t)
 :precision binary64
 (let* ((t_1 (sqrt (+ y 1.0)))
        (t_2 (- (sqrt (+ z 1.0)) (sqrt z)))
        (t_3 (/ 1.0 (+ t_1 (sqrt y))))
        (t_4 (- t_1 (sqrt y)))
        (t_5 (- (sqrt (+ x 1.0)) (sqrt x)))
        (t_6 (- (sqrt (+ t 1.0)) (sqrt t)))
        (t_7 (+ (+ (+ t_5 t_4) t_2) t_6)))
   (if (<= t_7 2e-5)
     (+ (+ (+ (* 0.5 (/ 1.0 (sqrt x))) t_3) t_2) t_6)
     (if (<= t_7 2.01)
       (+ (+ (+ t_5 t_3) (* 0.5 (/ 1.0 (sqrt z)))) (* 0.5 (/ 1.0 (sqrt t))))
       (+ (+ (+ (- (fma 0.5 x 1.0) (sqrt x)) t_4) t_2) t_6)))))
assert(x < y && y < z && z < t);
double code(double x, double y, double z, double t) {
	double t_1 = sqrt((y + 1.0));
	double t_2 = sqrt((z + 1.0)) - sqrt(z);
	double t_3 = 1.0 / (t_1 + sqrt(y));
	double t_4 = t_1 - sqrt(y);
	double t_5 = sqrt((x + 1.0)) - sqrt(x);
	double t_6 = sqrt((t + 1.0)) - sqrt(t);
	double t_7 = ((t_5 + t_4) + t_2) + t_6;
	double tmp;
	if (t_7 <= 2e-5) {
		tmp = (((0.5 * (1.0 / sqrt(x))) + t_3) + t_2) + t_6;
	} else if (t_7 <= 2.01) {
		tmp = ((t_5 + t_3) + (0.5 * (1.0 / sqrt(z)))) + (0.5 * (1.0 / sqrt(t)));
	} else {
		tmp = (((fma(0.5, x, 1.0) - sqrt(x)) + t_4) + t_2) + t_6;
	}
	return tmp;
}
x, y, z, t = sort([x, y, z, t])
function code(x, y, z, t)
	t_1 = sqrt(Float64(y + 1.0))
	t_2 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
	t_3 = Float64(1.0 / Float64(t_1 + sqrt(y)))
	t_4 = Float64(t_1 - sqrt(y))
	t_5 = Float64(sqrt(Float64(x + 1.0)) - sqrt(x))
	t_6 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
	t_7 = Float64(Float64(Float64(t_5 + t_4) + t_2) + t_6)
	tmp = 0.0
	if (t_7 <= 2e-5)
		tmp = Float64(Float64(Float64(Float64(0.5 * Float64(1.0 / sqrt(x))) + t_3) + t_2) + t_6);
	elseif (t_7 <= 2.01)
		tmp = Float64(Float64(Float64(t_5 + t_3) + Float64(0.5 * Float64(1.0 / sqrt(z)))) + Float64(0.5 * Float64(1.0 / sqrt(t))));
	else
		tmp = Float64(Float64(Float64(Float64(fma(0.5, x, 1.0) - sqrt(x)) + t_4) + t_2) + t_6);
	end
	return tmp
end
NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(1.0 / N[(t$95$1 + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(t$95$1 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$6 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$7 = N[(N[(N[(t$95$5 + t$95$4), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$6), $MachinePrecision]}, If[LessEqual[t$95$7, 2e-5], N[(N[(N[(N[(0.5 * N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$6), $MachinePrecision], If[LessEqual[t$95$7, 2.01], N[(N[(N[(t$95$5 + t$95$3), $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(N[(0.5 * x + 1.0), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$4), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$6), $MachinePrecision]]]]]]]]]]
\begin{array}{l}
[x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
\\
\begin{array}{l}
t_1 := \sqrt{y + 1}\\
t_2 := \sqrt{z + 1} - \sqrt{z}\\
t_3 := \frac{1}{t\_1 + \sqrt{y}}\\
t_4 := t\_1 - \sqrt{y}\\
t_5 := \sqrt{x + 1} - \sqrt{x}\\
t_6 := \sqrt{t + 1} - \sqrt{t}\\
t_7 := \left(\left(t\_5 + t\_4\right) + t\_2\right) + t\_6\\
\mathbf{if}\;t\_7 \leq 2 \cdot 10^{-5}:\\
\;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + t\_3\right) + t\_2\right) + t\_6\\

\mathbf{elif}\;t\_7 \leq 2.01:\\
\;\;\;\;\left(\left(t\_5 + t\_3\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + 0.5 \cdot \frac{1}{\sqrt{t}}\\

\mathbf{else}:\\
\;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_4\right) + t\_2\right) + t\_6\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2.00000000000000016e-5

    1. Initial program 7.4%

      \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
    2. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      2. lift-+.f64N/A

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      3. lift-sqrt.f64N/A

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      4. lift-sqrt.f64N/A

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      5. +-commutativeN/A

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      6. flip--N/A

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      7. lower-/.f64N/A

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
    3. Applied rewrites7.4%

      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
    4. Taylor expanded in y around 0

      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
    5. Step-by-step derivation
      1. Applied rewrites12.9%

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      2. Taylor expanded in x around inf

        \[\leadsto \left(\left(\color{blue}{\frac{1}{2} \cdot \sqrt{\frac{1}{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      3. Step-by-step derivation
        1. lower-*.f64N/A

          \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\sqrt{\frac{1}{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        2. sqrt-divN/A

          \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{\sqrt{1}}{\color{blue}{\sqrt{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        3. metadata-evalN/A

          \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{1}{\sqrt{\color{blue}{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        4. lower-/.f64N/A

          \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        5. lift-sqrt.f6495.9

          \[\leadsto \left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      4. Applied rewrites95.9%

        \[\leadsto \left(\left(\color{blue}{0.5 \cdot \frac{1}{\sqrt{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

      if 2.00000000000000016e-5 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2.0099999999999998

      1. Initial program 95.8%

        \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      2. Step-by-step derivation
        1. lift--.f64N/A

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        2. lift-+.f64N/A

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        3. lift-sqrt.f64N/A

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        4. lift-sqrt.f64N/A

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        5. +-commutativeN/A

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        6. flip--N/A

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        7. lower-/.f64N/A

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      3. Applied rewrites96.1%

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      4. Taylor expanded in y around 0

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      5. Step-by-step derivation
        1. Applied rewrites97.7%

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        2. Taylor expanded in z around inf

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \color{blue}{\frac{1}{2} \cdot \sqrt{\frac{1}{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        3. Step-by-step derivation
          1. lower-*.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \color{blue}{\sqrt{\frac{1}{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          2. sqrt-divN/A

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{\sqrt{1}}{\color{blue}{\sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          3. metadata-evalN/A

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{\color{blue}{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          4. lower-/.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          5. lift-sqrt.f6499.1

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        4. Applied rewrites99.1%

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \color{blue}{0.5 \cdot \frac{1}{\sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        5. Taylor expanded in t around inf

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \color{blue}{\frac{1}{2} \cdot \sqrt{\frac{1}{t}}} \]
        6. Step-by-step derivation
          1. lower-*.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \frac{1}{2} \cdot \color{blue}{\sqrt{\frac{1}{t}}} \]
          2. sqrt-divN/A

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \frac{1}{2} \cdot \frac{\sqrt{1}}{\color{blue}{\sqrt{t}}} \]
          3. metadata-evalN/A

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{\color{blue}{t}}} \]
          4. lower-/.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{t}}} \]
          5. lift-sqrt.f6499.1

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + 0.5 \cdot \frac{1}{\sqrt{t}} \]
        7. Applied rewrites99.1%

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + \color{blue}{0.5 \cdot \frac{1}{\sqrt{t}}} \]

        if 2.0099999999999998 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

        1. Initial program 98.5%

          \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        2. Taylor expanded in x around 0

          \[\leadsto \left(\left(\left(\color{blue}{\left(1 + \frac{1}{2} \cdot x\right)} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        3. Step-by-step derivation
          1. +-commutativeN/A

            \[\leadsto \left(\left(\left(\left(\frac{1}{2} \cdot x + \color{blue}{1}\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          2. lower-fma.f6498.5

            \[\leadsto \left(\left(\left(\mathsf{fma}\left(0.5, \color{blue}{x}, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        4. Applied rewrites98.5%

          \[\leadsto \left(\left(\left(\color{blue}{\mathsf{fma}\left(0.5, x, 1\right)} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      6. Recombined 3 regimes into one program.
      7. Add Preprocessing

      Alternative 2: 92.9% accurate, 0.3× speedup?

      \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1} - \sqrt{z}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ t_3 := \sqrt{y + 1} - \sqrt{y}\\ t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\ \mathbf{if}\;t\_4 \leq 1.0002:\\ \;\;\;\;\left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + t\_2\\ \mathbf{elif}\;t\_4 \leq 3.5:\\ \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_3\right) + t\_1\right) + 0.5 \cdot \frac{1}{\sqrt{t}}\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + \left(\mathsf{fma}\left(0.5, z, 1\right) - \sqrt{z}\right)\right) + t\_2\\ \end{array} \end{array} \]
      NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
      (FPCore (x y z t)
       :precision binary64
       (let* ((t_1 (- (sqrt (+ z 1.0)) (sqrt z)))
              (t_2 (- (sqrt (+ t 1.0)) (sqrt t)))
              (t_3 (- (sqrt (+ y 1.0)) (sqrt y)))
              (t_4 (+ (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) t_3) t_1) t_2)))
         (if (<= t_4 1.0002)
           (+ (- (+ (sqrt (+ 1.0 x)) (* 0.5 (/ 1.0 (sqrt y)))) (sqrt x)) t_2)
           (if (<= t_4 3.5)
             (+
              (+ (+ (- (fma 0.5 x 1.0) (sqrt x)) t_3) t_1)
              (* 0.5 (/ 1.0 (sqrt t))))
             (+ (+ (+ (- 1.0 (sqrt x)) t_3) (- (fma 0.5 z 1.0) (sqrt z))) t_2)))))
      assert(x < y && y < z && z < t);
      double code(double x, double y, double z, double t) {
      	double t_1 = sqrt((z + 1.0)) - sqrt(z);
      	double t_2 = sqrt((t + 1.0)) - sqrt(t);
      	double t_3 = sqrt((y + 1.0)) - sqrt(y);
      	double t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2;
      	double tmp;
      	if (t_4 <= 1.0002) {
      		tmp = ((sqrt((1.0 + x)) + (0.5 * (1.0 / sqrt(y)))) - sqrt(x)) + t_2;
      	} else if (t_4 <= 3.5) {
      		tmp = (((fma(0.5, x, 1.0) - sqrt(x)) + t_3) + t_1) + (0.5 * (1.0 / sqrt(t)));
      	} else {
      		tmp = (((1.0 - sqrt(x)) + t_3) + (fma(0.5, z, 1.0) - sqrt(z))) + t_2;
      	}
      	return tmp;
      }
      
      x, y, z, t = sort([x, y, z, t])
      function code(x, y, z, t)
      	t_1 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
      	t_2 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
      	t_3 = Float64(sqrt(Float64(y + 1.0)) - sqrt(y))
      	t_4 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2)
      	tmp = 0.0
      	if (t_4 <= 1.0002)
      		tmp = Float64(Float64(Float64(sqrt(Float64(1.0 + x)) + Float64(0.5 * Float64(1.0 / sqrt(y)))) - sqrt(x)) + t_2);
      	elseif (t_4 <= 3.5)
      		tmp = Float64(Float64(Float64(Float64(fma(0.5, x, 1.0) - sqrt(x)) + t_3) + t_1) + Float64(0.5 * Float64(1.0 / sqrt(t))));
      	else
      		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + t_3) + Float64(fma(0.5, z, 1.0) - sqrt(z))) + t_2);
      	end
      	return tmp
      end
      
      NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
      code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision]}, If[LessEqual[t$95$4, 1.0002], N[(N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision], If[LessEqual[t$95$4, 3.5], N[(N[(N[(N[(N[(0.5 * x + 1.0), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + N[(N[(0.5 * z + 1.0), $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision]]]]]]]
      
      \begin{array}{l}
      [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
      \\
      \begin{array}{l}
      t_1 := \sqrt{z + 1} - \sqrt{z}\\
      t_2 := \sqrt{t + 1} - \sqrt{t}\\
      t_3 := \sqrt{y + 1} - \sqrt{y}\\
      t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\
      \mathbf{if}\;t\_4 \leq 1.0002:\\
      \;\;\;\;\left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + t\_2\\
      
      \mathbf{elif}\;t\_4 \leq 3.5:\\
      \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_3\right) + t\_1\right) + 0.5 \cdot \frac{1}{\sqrt{t}}\\
      
      \mathbf{else}:\\
      \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + \left(\mathsf{fma}\left(0.5, z, 1\right) - \sqrt{z}\right)\right) + t\_2\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.0002

        1. Initial program 78.4%

          \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        2. Taylor expanded in z around inf

          \[\leadsto \color{blue}{\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        3. Step-by-step derivation
          1. associate--r+N/A

            \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          2. lower--.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          3. lower--.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          4. lower-+.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          5. +-commutativeN/A

            \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          6. lift-sqrt.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          7. +-commutativeN/A

            \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          8. lower-+.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          9. +-commutativeN/A

            \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          10. lift-sqrt.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          11. lift-+.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          12. lift-sqrt.f64N/A

            \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          13. lift-sqrt.f6417.3

            \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        4. Applied rewrites17.3%

          \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        5. Taylor expanded in y around inf

          \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        6. Step-by-step derivation
          1. lower--.f64N/A

            \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          2. lower-+.f64N/A

            \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          3. lift-sqrt.f64N/A

            \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          4. lift-+.f64N/A

            \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          5. lower-*.f64N/A

            \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          6. sqrt-divN/A

            \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{\sqrt{1}}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          7. metadata-evalN/A

            \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          8. lower-/.f64N/A

            \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          9. lift-sqrt.f64N/A

            \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          10. lift-sqrt.f6481.7

            \[\leadsto \left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        7. Applied rewrites81.7%

          \[\leadsto \left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

        if 1.0002 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 3.5

        1. Initial program 97.3%

          \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        2. Taylor expanded in x around 0

          \[\leadsto \left(\left(\left(\color{blue}{\left(1 + \frac{1}{2} \cdot x\right)} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        3. Step-by-step derivation
          1. +-commutativeN/A

            \[\leadsto \left(\left(\left(\left(\frac{1}{2} \cdot x + \color{blue}{1}\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          2. lower-fma.f6497.3

            \[\leadsto \left(\left(\left(\mathsf{fma}\left(0.5, \color{blue}{x}, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        4. Applied rewrites97.3%

          \[\leadsto \left(\left(\left(\color{blue}{\mathsf{fma}\left(0.5, x, 1\right)} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        5. Taylor expanded in t around inf

          \[\leadsto \left(\left(\left(\mathsf{fma}\left(\frac{1}{2}, x, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \color{blue}{\frac{1}{2} \cdot \sqrt{\frac{1}{t}}} \]
        6. Step-by-step derivation
          1. lower-*.f64N/A

            \[\leadsto \left(\left(\left(\mathsf{fma}\left(\frac{1}{2}, x, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \frac{1}{2} \cdot \color{blue}{\sqrt{\frac{1}{t}}} \]
          2. sqrt-divN/A

            \[\leadsto \left(\left(\left(\mathsf{fma}\left(\frac{1}{2}, x, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \frac{1}{2} \cdot \frac{\sqrt{1}}{\color{blue}{\sqrt{t}}} \]
          3. metadata-evalN/A

            \[\leadsto \left(\left(\left(\mathsf{fma}\left(\frac{1}{2}, x, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{\color{blue}{t}}} \]
          4. lower-/.f64N/A

            \[\leadsto \left(\left(\left(\mathsf{fma}\left(\frac{1}{2}, x, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{t}}} \]
          5. lift-sqrt.f6497.5

            \[\leadsto \left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + 0.5 \cdot \frac{1}{\sqrt{t}} \]
        7. Applied rewrites97.5%

          \[\leadsto \left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \color{blue}{0.5 \cdot \frac{1}{\sqrt{t}}} \]

        if 3.5 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

        1. Initial program 99.9%

          \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        2. Taylor expanded in z around 0

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\color{blue}{\left(1 + \frac{1}{2} \cdot z\right)} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        3. Step-by-step derivation
          1. +-commutativeN/A

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\frac{1}{2} \cdot z + \color{blue}{1}\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          2. lower-fma.f6499.7

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\mathsf{fma}\left(0.5, \color{blue}{z}, 1\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        4. Applied rewrites99.7%

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\color{blue}{\mathsf{fma}\left(0.5, z, 1\right)} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        5. Taylor expanded in x around 0

          \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\mathsf{fma}\left(\frac{1}{2}, z, 1\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        6. Step-by-step derivation
          1. Applied rewrites99.7%

            \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\mathsf{fma}\left(0.5, z, 1\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        7. Recombined 3 regimes into one program.
        8. Add Preprocessing

        Alternative 3: 92.7% accurate, 0.3× speedup?

        \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1} - \sqrt{z}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ t_3 := \sqrt{y + 1} - \sqrt{y}\\ t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\ \mathbf{if}\;t\_4 \leq 1.0002:\\ \;\;\;\;\left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + t\_2\\ \mathbf{elif}\;t\_4 \leq 2.995:\\ \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_3\right) + t\_1\right) + \left(\sqrt{t} - \sqrt{t}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + \left(\mathsf{fma}\left(0.5, z, 1\right) - \sqrt{z}\right)\right) + t\_2\\ \end{array} \end{array} \]
        NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
        (FPCore (x y z t)
         :precision binary64
         (let* ((t_1 (- (sqrt (+ z 1.0)) (sqrt z)))
                (t_2 (- (sqrt (+ t 1.0)) (sqrt t)))
                (t_3 (- (sqrt (+ y 1.0)) (sqrt y)))
                (t_4 (+ (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) t_3) t_1) t_2)))
           (if (<= t_4 1.0002)
             (+ (- (+ (sqrt (+ 1.0 x)) (* 0.5 (/ 1.0 (sqrt y)))) (sqrt x)) t_2)
             (if (<= t_4 2.995)
               (+ (+ (+ (- (fma 0.5 x 1.0) (sqrt x)) t_3) t_1) (- (sqrt t) (sqrt t)))
               (+ (+ (+ (- 1.0 (sqrt x)) t_3) (- (fma 0.5 z 1.0) (sqrt z))) t_2)))))
        assert(x < y && y < z && z < t);
        double code(double x, double y, double z, double t) {
        	double t_1 = sqrt((z + 1.0)) - sqrt(z);
        	double t_2 = sqrt((t + 1.0)) - sqrt(t);
        	double t_3 = sqrt((y + 1.0)) - sqrt(y);
        	double t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2;
        	double tmp;
        	if (t_4 <= 1.0002) {
        		tmp = ((sqrt((1.0 + x)) + (0.5 * (1.0 / sqrt(y)))) - sqrt(x)) + t_2;
        	} else if (t_4 <= 2.995) {
        		tmp = (((fma(0.5, x, 1.0) - sqrt(x)) + t_3) + t_1) + (sqrt(t) - sqrt(t));
        	} else {
        		tmp = (((1.0 - sqrt(x)) + t_3) + (fma(0.5, z, 1.0) - sqrt(z))) + t_2;
        	}
        	return tmp;
        }
        
        x, y, z, t = sort([x, y, z, t])
        function code(x, y, z, t)
        	t_1 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
        	t_2 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
        	t_3 = Float64(sqrt(Float64(y + 1.0)) - sqrt(y))
        	t_4 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2)
        	tmp = 0.0
        	if (t_4 <= 1.0002)
        		tmp = Float64(Float64(Float64(sqrt(Float64(1.0 + x)) + Float64(0.5 * Float64(1.0 / sqrt(y)))) - sqrt(x)) + t_2);
        	elseif (t_4 <= 2.995)
        		tmp = Float64(Float64(Float64(Float64(fma(0.5, x, 1.0) - sqrt(x)) + t_3) + t_1) + Float64(sqrt(t) - sqrt(t)));
        	else
        		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + t_3) + Float64(fma(0.5, z, 1.0) - sqrt(z))) + t_2);
        	end
        	return tmp
        end
        
        NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
        code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision]}, If[LessEqual[t$95$4, 1.0002], N[(N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision], If[LessEqual[t$95$4, 2.995], N[(N[(N[(N[(N[(0.5 * x + 1.0), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + N[(N[Sqrt[t], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + N[(N[(0.5 * z + 1.0), $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision]]]]]]]
        
        \begin{array}{l}
        [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
        \\
        \begin{array}{l}
        t_1 := \sqrt{z + 1} - \sqrt{z}\\
        t_2 := \sqrt{t + 1} - \sqrt{t}\\
        t_3 := \sqrt{y + 1} - \sqrt{y}\\
        t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\
        \mathbf{if}\;t\_4 \leq 1.0002:\\
        \;\;\;\;\left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + t\_2\\
        
        \mathbf{elif}\;t\_4 \leq 2.995:\\
        \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_3\right) + t\_1\right) + \left(\sqrt{t} - \sqrt{t}\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + \left(\mathsf{fma}\left(0.5, z, 1\right) - \sqrt{z}\right)\right) + t\_2\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 3 regimes
        2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.0002

          1. Initial program 78.4%

            \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          2. Taylor expanded in z around inf

            \[\leadsto \color{blue}{\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          3. Step-by-step derivation
            1. associate--r+N/A

              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. lower--.f64N/A

              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            3. lower--.f64N/A

              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            4. lower-+.f64N/A

              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            5. +-commutativeN/A

              \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            6. lift-sqrt.f64N/A

              \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            7. +-commutativeN/A

              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            8. lower-+.f64N/A

              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            9. +-commutativeN/A

              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            10. lift-sqrt.f64N/A

              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            11. lift-+.f64N/A

              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            12. lift-sqrt.f64N/A

              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            13. lift-sqrt.f6417.3

              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          4. Applied rewrites17.3%

            \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          5. Taylor expanded in y around inf

            \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          6. Step-by-step derivation
            1. lower--.f64N/A

              \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. lower-+.f64N/A

              \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            3. lift-sqrt.f64N/A

              \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            4. lift-+.f64N/A

              \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            5. lower-*.f64N/A

              \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            6. sqrt-divN/A

              \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{\sqrt{1}}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            7. metadata-evalN/A

              \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            8. lower-/.f64N/A

              \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            9. lift-sqrt.f64N/A

              \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            10. lift-sqrt.f6481.7

              \[\leadsto \left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          7. Applied rewrites81.7%

            \[\leadsto \left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

          if 1.0002 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2.9950000000000001

          1. Initial program 96.7%

            \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          2. Taylor expanded in x around 0

            \[\leadsto \left(\left(\left(\color{blue}{\left(1 + \frac{1}{2} \cdot x\right)} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          3. Step-by-step derivation
            1. +-commutativeN/A

              \[\leadsto \left(\left(\left(\left(\frac{1}{2} \cdot x + \color{blue}{1}\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. lower-fma.f6496.6

              \[\leadsto \left(\left(\left(\mathsf{fma}\left(0.5, \color{blue}{x}, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          4. Applied rewrites96.6%

            \[\leadsto \left(\left(\left(\color{blue}{\mathsf{fma}\left(0.5, x, 1\right)} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          5. Taylor expanded in t around inf

            \[\leadsto \left(\left(\left(\mathsf{fma}\left(\frac{1}{2}, x, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{\color{blue}{t}} - \sqrt{t}\right) \]
          6. Step-by-step derivation
            1. Applied rewrites96.6%

              \[\leadsto \left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{\color{blue}{t}} - \sqrt{t}\right) \]

            if 2.9950000000000001 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

            1. Initial program 98.6%

              \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. Taylor expanded in z around 0

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\color{blue}{\left(1 + \frac{1}{2} \cdot z\right)} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            3. Step-by-step derivation
              1. +-commutativeN/A

                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\frac{1}{2} \cdot z + \color{blue}{1}\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. lower-fma.f6498.3

                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\mathsf{fma}\left(0.5, \color{blue}{z}, 1\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            4. Applied rewrites98.3%

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\color{blue}{\mathsf{fma}\left(0.5, z, 1\right)} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            5. Taylor expanded in x around 0

              \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\mathsf{fma}\left(\frac{1}{2}, z, 1\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            6. Step-by-step derivation
              1. Applied rewrites98.3%

                \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\mathsf{fma}\left(0.5, z, 1\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            7. Recombined 3 regimes into one program.
            8. Add Preprocessing

            Alternative 4: 90.6% accurate, 0.3× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{1 + x}\\ t_3 := \sqrt{t + 1} - \sqrt{t}\\ t_4 := t\_1 - \sqrt{y}\\ t_5 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_4\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + t\_3\\ \mathbf{if}\;t\_5 \leq 1.0002:\\ \;\;\;\;\left(\left(t\_2 + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + t\_3\\ \mathbf{elif}\;t\_5 \leq 2.5:\\ \;\;\;\;\left(\left(\left(t\_2 + t\_1\right) - \sqrt{x}\right) - \sqrt{y}\right) + 0.5 \cdot \frac{1}{\sqrt{t}}\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_4\right) + \left(\mathsf{fma}\left(0.5, z, 1\right) - \sqrt{z}\right)\right) + t\_3\\ \end{array} \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t)
             :precision binary64
             (let* ((t_1 (sqrt (+ y 1.0)))
                    (t_2 (sqrt (+ 1.0 x)))
                    (t_3 (- (sqrt (+ t 1.0)) (sqrt t)))
                    (t_4 (- t_1 (sqrt y)))
                    (t_5
                     (+
                      (+
                       (+ (- (sqrt (+ x 1.0)) (sqrt x)) t_4)
                       (- (sqrt (+ z 1.0)) (sqrt z)))
                      t_3)))
               (if (<= t_5 1.0002)
                 (+ (- (+ t_2 (* 0.5 (/ 1.0 (sqrt y)))) (sqrt x)) t_3)
                 (if (<= t_5 2.5)
                   (+ (- (- (+ t_2 t_1) (sqrt x)) (sqrt y)) (* 0.5 (/ 1.0 (sqrt t))))
                   (+ (+ (+ (- 1.0 (sqrt x)) t_4) (- (fma 0.5 z 1.0) (sqrt z))) t_3)))))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	double t_1 = sqrt((y + 1.0));
            	double t_2 = sqrt((1.0 + x));
            	double t_3 = sqrt((t + 1.0)) - sqrt(t);
            	double t_4 = t_1 - sqrt(y);
            	double t_5 = (((sqrt((x + 1.0)) - sqrt(x)) + t_4) + (sqrt((z + 1.0)) - sqrt(z))) + t_3;
            	double tmp;
            	if (t_5 <= 1.0002) {
            		tmp = ((t_2 + (0.5 * (1.0 / sqrt(y)))) - sqrt(x)) + t_3;
            	} else if (t_5 <= 2.5) {
            		tmp = (((t_2 + t_1) - sqrt(x)) - sqrt(y)) + (0.5 * (1.0 / sqrt(t)));
            	} else {
            		tmp = (((1.0 - sqrt(x)) + t_4) + (fma(0.5, z, 1.0) - sqrt(z))) + t_3;
            	}
            	return tmp;
            }
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	t_1 = sqrt(Float64(y + 1.0))
            	t_2 = sqrt(Float64(1.0 + x))
            	t_3 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
            	t_4 = Float64(t_1 - sqrt(y))
            	t_5 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + t_4) + Float64(sqrt(Float64(z + 1.0)) - sqrt(z))) + t_3)
            	tmp = 0.0
            	if (t_5 <= 1.0002)
            		tmp = Float64(Float64(Float64(t_2 + Float64(0.5 * Float64(1.0 / sqrt(y)))) - sqrt(x)) + t_3);
            	elseif (t_5 <= 2.5)
            		tmp = Float64(Float64(Float64(Float64(t_2 + t_1) - sqrt(x)) - sqrt(y)) + Float64(0.5 * Float64(1.0 / sqrt(t))));
            	else
            		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + t_4) + Float64(fma(0.5, z, 1.0) - sqrt(z))) + t_3);
            	end
            	return tmp
            end
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(t$95$1 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$4), $MachinePrecision] + N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision]}, If[LessEqual[t$95$5, 1.0002], N[(N[(N[(t$95$2 + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision], If[LessEqual[t$95$5, 2.5], N[(N[(N[(N[(t$95$2 + t$95$1), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$4), $MachinePrecision] + N[(N[(0.5 * z + 1.0), $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision]]]]]]]]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \begin{array}{l}
            t_1 := \sqrt{y + 1}\\
            t_2 := \sqrt{1 + x}\\
            t_3 := \sqrt{t + 1} - \sqrt{t}\\
            t_4 := t\_1 - \sqrt{y}\\
            t_5 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_4\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + t\_3\\
            \mathbf{if}\;t\_5 \leq 1.0002:\\
            \;\;\;\;\left(\left(t\_2 + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + t\_3\\
            
            \mathbf{elif}\;t\_5 \leq 2.5:\\
            \;\;\;\;\left(\left(\left(t\_2 + t\_1\right) - \sqrt{x}\right) - \sqrt{y}\right) + 0.5 \cdot \frac{1}{\sqrt{t}}\\
            
            \mathbf{else}:\\
            \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_4\right) + \left(\mathsf{fma}\left(0.5, z, 1\right) - \sqrt{z}\right)\right) + t\_3\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 3 regimes
            2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.0002

              1. Initial program 78.4%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Taylor expanded in z around inf

                \[\leadsto \color{blue}{\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              3. Step-by-step derivation
                1. associate--r+N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. lower--.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                3. lower--.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                4. lower-+.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                5. +-commutativeN/A

                  \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                6. lift-sqrt.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                7. +-commutativeN/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                8. lower-+.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                9. +-commutativeN/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                10. lift-sqrt.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                11. lift-+.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                12. lift-sqrt.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                13. lift-sqrt.f6417.3

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              4. Applied rewrites17.3%

                \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              5. Taylor expanded in y around inf

                \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              6. Step-by-step derivation
                1. lower--.f64N/A

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. lower-+.f64N/A

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                3. lift-sqrt.f64N/A

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                4. lift-+.f64N/A

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                5. lower-*.f64N/A

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                6. sqrt-divN/A

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{\sqrt{1}}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                7. metadata-evalN/A

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                8. lower-/.f64N/A

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                9. lift-sqrt.f64N/A

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                10. lift-sqrt.f6481.7

                  \[\leadsto \left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              7. Applied rewrites81.7%

                \[\leadsto \left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

              if 1.0002 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2.5

              1. Initial program 96.6%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Taylor expanded in z around inf

                \[\leadsto \color{blue}{\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              3. Step-by-step derivation
                1. associate--r+N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. lower--.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                3. lower--.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                4. lower-+.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                5. +-commutativeN/A

                  \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                6. lift-sqrt.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                7. +-commutativeN/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                8. lower-+.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                9. +-commutativeN/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                10. lift-sqrt.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                11. lift-+.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                12. lift-sqrt.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                13. lift-sqrt.f6492.2

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              4. Applied rewrites92.2%

                \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              5. Taylor expanded in t around inf

                \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \color{blue}{\frac{1}{2} \cdot \sqrt{\frac{1}{t}}} \]
              6. Step-by-step derivation
                1. lower-*.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \frac{1}{2} \cdot \color{blue}{\sqrt{\frac{1}{t}}} \]
                2. sqrt-divN/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \frac{1}{2} \cdot \frac{\sqrt{1}}{\color{blue}{\sqrt{t}}} \]
                3. metadata-evalN/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{\color{blue}{t}}} \]
                4. lower-/.f64N/A

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{t}}} \]
                5. lift-sqrt.f6492.2

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + 0.5 \cdot \frac{1}{\sqrt{t}} \]
              7. Applied rewrites92.2%

                \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \color{blue}{0.5 \cdot \frac{1}{\sqrt{t}}} \]

              if 2.5 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

              1. Initial program 98.6%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Taylor expanded in z around 0

                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\color{blue}{\left(1 + \frac{1}{2} \cdot z\right)} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              3. Step-by-step derivation
                1. +-commutativeN/A

                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\frac{1}{2} \cdot z + \color{blue}{1}\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. lower-fma.f6497.0

                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\mathsf{fma}\left(0.5, \color{blue}{z}, 1\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              4. Applied rewrites97.0%

                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\color{blue}{\mathsf{fma}\left(0.5, z, 1\right)} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              5. Taylor expanded in x around 0

                \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\mathsf{fma}\left(\frac{1}{2}, z, 1\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              6. Step-by-step derivation
                1. Applied rewrites97.0%

                  \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\mathsf{fma}\left(0.5, z, 1\right) - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              7. Recombined 3 regimes into one program.
              8. Add Preprocessing

              Alternative 5: 87.0% accurate, 0.4× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{1 + x}\\ t_3 := \sqrt{z + 1}\\ t_4 := \sqrt{t + 1} - \sqrt{t}\\ t_5 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_3 - \sqrt{z}\right)\right) + t\_4\\ \mathbf{if}\;t\_5 \leq 1.0002:\\ \;\;\;\;\left(\left(t\_2 + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + t\_4\\ \mathbf{elif}\;t\_5 \leq 2:\\ \;\;\;\;\left(t\_2 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\left(1 + 0.5 \cdot x\right) + t\_1\right) + t\_3\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)\\ \end{array} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t)
               :precision binary64
               (let* ((t_1 (sqrt (+ y 1.0)))
                      (t_2 (sqrt (+ 1.0 x)))
                      (t_3 (sqrt (+ z 1.0)))
                      (t_4 (- (sqrt (+ t 1.0)) (sqrt t)))
                      (t_5
                       (+
                        (+
                         (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- t_1 (sqrt y)))
                         (- t_3 (sqrt z)))
                        t_4)))
                 (if (<= t_5 1.0002)
                   (+ (- (+ t_2 (* 0.5 (/ 1.0 (sqrt y)))) (sqrt x)) t_4)
                   (if (<= t_5 2.0)
                     (- (+ t_2 (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                     (-
                      (- (+ (+ (+ 1.0 (* 0.5 x)) t_1) t_3) (sqrt x))
                      (+ (sqrt z) (sqrt y)))))))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	double t_1 = sqrt((y + 1.0));
              	double t_2 = sqrt((1.0 + x));
              	double t_3 = sqrt((z + 1.0));
              	double t_4 = sqrt((t + 1.0)) - sqrt(t);
              	double t_5 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_1 - sqrt(y))) + (t_3 - sqrt(z))) + t_4;
              	double tmp;
              	if (t_5 <= 1.0002) {
              		tmp = ((t_2 + (0.5 * (1.0 / sqrt(y)))) - sqrt(x)) + t_4;
              	} else if (t_5 <= 2.0) {
              		tmp = (t_2 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
              	} else {
              		tmp = ((((1.0 + (0.5 * x)) + t_1) + t_3) - sqrt(x)) - (sqrt(z) + sqrt(y));
              	}
              	return tmp;
              }
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(x, y, z, t)
              use fmin_fmax_functions
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  real(8) :: t_1
                  real(8) :: t_2
                  real(8) :: t_3
                  real(8) :: t_4
                  real(8) :: t_5
                  real(8) :: tmp
                  t_1 = sqrt((y + 1.0d0))
                  t_2 = sqrt((1.0d0 + x))
                  t_3 = sqrt((z + 1.0d0))
                  t_4 = sqrt((t + 1.0d0)) - sqrt(t)
                  t_5 = (((sqrt((x + 1.0d0)) - sqrt(x)) + (t_1 - sqrt(y))) + (t_3 - sqrt(z))) + t_4
                  if (t_5 <= 1.0002d0) then
                      tmp = ((t_2 + (0.5d0 * (1.0d0 / sqrt(y)))) - sqrt(x)) + t_4
                  else if (t_5 <= 2.0d0) then
                      tmp = (t_2 + sqrt((1.0d0 + y))) - (sqrt(x) + sqrt(y))
                  else
                      tmp = ((((1.0d0 + (0.5d0 * x)) + t_1) + t_3) - sqrt(x)) - (sqrt(z) + sqrt(y))
                  end if
                  code = tmp
              end function
              
              assert x < y && y < z && z < t;
              public static double code(double x, double y, double z, double t) {
              	double t_1 = Math.sqrt((y + 1.0));
              	double t_2 = Math.sqrt((1.0 + x));
              	double t_3 = Math.sqrt((z + 1.0));
              	double t_4 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
              	double t_5 = (((Math.sqrt((x + 1.0)) - Math.sqrt(x)) + (t_1 - Math.sqrt(y))) + (t_3 - Math.sqrt(z))) + t_4;
              	double tmp;
              	if (t_5 <= 1.0002) {
              		tmp = ((t_2 + (0.5 * (1.0 / Math.sqrt(y)))) - Math.sqrt(x)) + t_4;
              	} else if (t_5 <= 2.0) {
              		tmp = (t_2 + Math.sqrt((1.0 + y))) - (Math.sqrt(x) + Math.sqrt(y));
              	} else {
              		tmp = ((((1.0 + (0.5 * x)) + t_1) + t_3) - Math.sqrt(x)) - (Math.sqrt(z) + Math.sqrt(y));
              	}
              	return tmp;
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	t_1 = math.sqrt((y + 1.0))
              	t_2 = math.sqrt((1.0 + x))
              	t_3 = math.sqrt((z + 1.0))
              	t_4 = math.sqrt((t + 1.0)) - math.sqrt(t)
              	t_5 = (((math.sqrt((x + 1.0)) - math.sqrt(x)) + (t_1 - math.sqrt(y))) + (t_3 - math.sqrt(z))) + t_4
              	tmp = 0
              	if t_5 <= 1.0002:
              		tmp = ((t_2 + (0.5 * (1.0 / math.sqrt(y)))) - math.sqrt(x)) + t_4
              	elif t_5 <= 2.0:
              		tmp = (t_2 + math.sqrt((1.0 + y))) - (math.sqrt(x) + math.sqrt(y))
              	else:
              		tmp = ((((1.0 + (0.5 * x)) + t_1) + t_3) - math.sqrt(x)) - (math.sqrt(z) + math.sqrt(y))
              	return tmp
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	t_1 = sqrt(Float64(y + 1.0))
              	t_2 = sqrt(Float64(1.0 + x))
              	t_3 = sqrt(Float64(z + 1.0))
              	t_4 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
              	t_5 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(t_1 - sqrt(y))) + Float64(t_3 - sqrt(z))) + t_4)
              	tmp = 0.0
              	if (t_5 <= 1.0002)
              		tmp = Float64(Float64(Float64(t_2 + Float64(0.5 * Float64(1.0 / sqrt(y)))) - sqrt(x)) + t_4);
              	elseif (t_5 <= 2.0)
              		tmp = Float64(Float64(t_2 + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
              	else
              		tmp = Float64(Float64(Float64(Float64(Float64(1.0 + Float64(0.5 * x)) + t_1) + t_3) - sqrt(x)) - Float64(sqrt(z) + sqrt(y)));
              	end
              	return tmp
              end
              
              x, y, z, t = num2cell(sort([x, y, z, t])){:}
              function tmp_2 = code(x, y, z, t)
              	t_1 = sqrt((y + 1.0));
              	t_2 = sqrt((1.0 + x));
              	t_3 = sqrt((z + 1.0));
              	t_4 = sqrt((t + 1.0)) - sqrt(t);
              	t_5 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_1 - sqrt(y))) + (t_3 - sqrt(z))) + t_4;
              	tmp = 0.0;
              	if (t_5 <= 1.0002)
              		tmp = ((t_2 + (0.5 * (1.0 / sqrt(y)))) - sqrt(x)) + t_4;
              	elseif (t_5 <= 2.0)
              		tmp = (t_2 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
              	else
              		tmp = ((((1.0 + (0.5 * x)) + t_1) + t_3) - sqrt(x)) - (sqrt(z) + sqrt(y));
              	end
              	tmp_2 = tmp;
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$4 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(t$95$1 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$3 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$4), $MachinePrecision]}, If[LessEqual[t$95$5, 1.0002], N[(N[(N[(t$95$2 + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$4), $MachinePrecision], If[LessEqual[t$95$5, 2.0], N[(N[(t$95$2 + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(N[(1.0 + N[(0.5 * x), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$3), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[z], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \begin{array}{l}
              t_1 := \sqrt{y + 1}\\
              t_2 := \sqrt{1 + x}\\
              t_3 := \sqrt{z + 1}\\
              t_4 := \sqrt{t + 1} - \sqrt{t}\\
              t_5 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_3 - \sqrt{z}\right)\right) + t\_4\\
              \mathbf{if}\;t\_5 \leq 1.0002:\\
              \;\;\;\;\left(\left(t\_2 + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + t\_4\\
              
              \mathbf{elif}\;t\_5 \leq 2:\\
              \;\;\;\;\left(t\_2 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(\left(\left(\left(1 + 0.5 \cdot x\right) + t\_1\right) + t\_3\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 3 regimes
              2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.0002

                1. Initial program 78.4%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in z around inf

                  \[\leadsto \color{blue}{\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. lower--.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  4. lower-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  5. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  6. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  7. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  8. lower-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  9. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  10. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  11. lift-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  12. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  13. lift-sqrt.f6417.3

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                4. Applied rewrites17.3%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                5. Taylor expanded in y around inf

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                6. Step-by-step derivation
                  1. lower--.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. lower-+.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  4. lift-+.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  5. lower-*.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  6. sqrt-divN/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{\sqrt{1}}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  7. metadata-evalN/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  8. lower-/.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  9. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  10. lift-sqrt.f6481.7

                    \[\leadsto \left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                7. Applied rewrites81.7%

                  \[\leadsto \left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                if 1.0002 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2

                1. Initial program 97.7%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in t around inf

                  \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites12.1%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                5. Taylor expanded in z around inf

                  \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                6. Step-by-step derivation
                  1. lower--.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \color{blue}{\sqrt{y}}\right) \]
                  2. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{\color{blue}{y}}\right) \]
                  3. lift-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  4. lift-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  5. lower-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  6. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  7. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  8. lift-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  9. lift-sqrt.f6497.2

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                7. Applied rewrites97.2%

                  \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]

                if 2 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

                1. Initial program 97.3%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in t around inf

                  \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites81.1%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                5. Taylor expanded in x around 0

                  \[\leadsto \left(\left(\left(\left(1 + \frac{1}{2} \cdot x\right) + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
                6. Step-by-step derivation
                  1. lower-+.f64N/A

                    \[\leadsto \left(\left(\left(\left(1 + \frac{1}{2} \cdot x\right) + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
                  2. lower-*.f6481.1

                    \[\leadsto \left(\left(\left(\left(1 + 0.5 \cdot x\right) + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
                7. Applied rewrites81.1%

                  \[\leadsto \left(\left(\left(\left(1 + 0.5 \cdot x\right) + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
              3. Recombined 3 regimes into one program.
              4. Add Preprocessing

              Alternative 6: 86.0% accurate, 0.4× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ t_3 := \sqrt{y + 1}\\ t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_3 - \sqrt{y}\right)\right) + \left(t\_1 - \sqrt{z}\right)\right) + t\_2\\ t_5 := \sqrt{1 + x}\\ \mathbf{if}\;t\_4 \leq 1:\\ \;\;\;\;\left(t\_5 - \sqrt{x}\right) + t\_2\\ \mathbf{elif}\;t\_4 \leq 2:\\ \;\;\;\;\left(t\_5 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\left(1 + 0.5 \cdot x\right) + t\_3\right) + t\_1\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)\\ \end{array} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t)
               :precision binary64
               (let* ((t_1 (sqrt (+ z 1.0)))
                      (t_2 (- (sqrt (+ t 1.0)) (sqrt t)))
                      (t_3 (sqrt (+ y 1.0)))
                      (t_4
                       (+
                        (+
                         (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- t_3 (sqrt y)))
                         (- t_1 (sqrt z)))
                        t_2))
                      (t_5 (sqrt (+ 1.0 x))))
                 (if (<= t_4 1.0)
                   (+ (- t_5 (sqrt x)) t_2)
                   (if (<= t_4 2.0)
                     (- (+ t_5 (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                     (-
                      (- (+ (+ (+ 1.0 (* 0.5 x)) t_3) t_1) (sqrt x))
                      (+ (sqrt z) (sqrt y)))))))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	double t_1 = sqrt((z + 1.0));
              	double t_2 = sqrt((t + 1.0)) - sqrt(t);
              	double t_3 = sqrt((y + 1.0));
              	double t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_3 - sqrt(y))) + (t_1 - sqrt(z))) + t_2;
              	double t_5 = sqrt((1.0 + x));
              	double tmp;
              	if (t_4 <= 1.0) {
              		tmp = (t_5 - sqrt(x)) + t_2;
              	} else if (t_4 <= 2.0) {
              		tmp = (t_5 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
              	} else {
              		tmp = ((((1.0 + (0.5 * x)) + t_3) + t_1) - sqrt(x)) - (sqrt(z) + sqrt(y));
              	}
              	return tmp;
              }
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(x, y, z, t)
              use fmin_fmax_functions
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  real(8) :: t_1
                  real(8) :: t_2
                  real(8) :: t_3
                  real(8) :: t_4
                  real(8) :: t_5
                  real(8) :: tmp
                  t_1 = sqrt((z + 1.0d0))
                  t_2 = sqrt((t + 1.0d0)) - sqrt(t)
                  t_3 = sqrt((y + 1.0d0))
                  t_4 = (((sqrt((x + 1.0d0)) - sqrt(x)) + (t_3 - sqrt(y))) + (t_1 - sqrt(z))) + t_2
                  t_5 = sqrt((1.0d0 + x))
                  if (t_4 <= 1.0d0) then
                      tmp = (t_5 - sqrt(x)) + t_2
                  else if (t_4 <= 2.0d0) then
                      tmp = (t_5 + sqrt((1.0d0 + y))) - (sqrt(x) + sqrt(y))
                  else
                      tmp = ((((1.0d0 + (0.5d0 * x)) + t_3) + t_1) - sqrt(x)) - (sqrt(z) + sqrt(y))
                  end if
                  code = tmp
              end function
              
              assert x < y && y < z && z < t;
              public static double code(double x, double y, double z, double t) {
              	double t_1 = Math.sqrt((z + 1.0));
              	double t_2 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
              	double t_3 = Math.sqrt((y + 1.0));
              	double t_4 = (((Math.sqrt((x + 1.0)) - Math.sqrt(x)) + (t_3 - Math.sqrt(y))) + (t_1 - Math.sqrt(z))) + t_2;
              	double t_5 = Math.sqrt((1.0 + x));
              	double tmp;
              	if (t_4 <= 1.0) {
              		tmp = (t_5 - Math.sqrt(x)) + t_2;
              	} else if (t_4 <= 2.0) {
              		tmp = (t_5 + Math.sqrt((1.0 + y))) - (Math.sqrt(x) + Math.sqrt(y));
              	} else {
              		tmp = ((((1.0 + (0.5 * x)) + t_3) + t_1) - Math.sqrt(x)) - (Math.sqrt(z) + Math.sqrt(y));
              	}
              	return tmp;
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	t_1 = math.sqrt((z + 1.0))
              	t_2 = math.sqrt((t + 1.0)) - math.sqrt(t)
              	t_3 = math.sqrt((y + 1.0))
              	t_4 = (((math.sqrt((x + 1.0)) - math.sqrt(x)) + (t_3 - math.sqrt(y))) + (t_1 - math.sqrt(z))) + t_2
              	t_5 = math.sqrt((1.0 + x))
              	tmp = 0
              	if t_4 <= 1.0:
              		tmp = (t_5 - math.sqrt(x)) + t_2
              	elif t_4 <= 2.0:
              		tmp = (t_5 + math.sqrt((1.0 + y))) - (math.sqrt(x) + math.sqrt(y))
              	else:
              		tmp = ((((1.0 + (0.5 * x)) + t_3) + t_1) - math.sqrt(x)) - (math.sqrt(z) + math.sqrt(y))
              	return tmp
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	t_1 = sqrt(Float64(z + 1.0))
              	t_2 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
              	t_3 = sqrt(Float64(y + 1.0))
              	t_4 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(t_3 - sqrt(y))) + Float64(t_1 - sqrt(z))) + t_2)
              	t_5 = sqrt(Float64(1.0 + x))
              	tmp = 0.0
              	if (t_4 <= 1.0)
              		tmp = Float64(Float64(t_5 - sqrt(x)) + t_2);
              	elseif (t_4 <= 2.0)
              		tmp = Float64(Float64(t_5 + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
              	else
              		tmp = Float64(Float64(Float64(Float64(Float64(1.0 + Float64(0.5 * x)) + t_3) + t_1) - sqrt(x)) - Float64(sqrt(z) + sqrt(y)));
              	end
              	return tmp
              end
              
              x, y, z, t = num2cell(sort([x, y, z, t])){:}
              function tmp_2 = code(x, y, z, t)
              	t_1 = sqrt((z + 1.0));
              	t_2 = sqrt((t + 1.0)) - sqrt(t);
              	t_3 = sqrt((y + 1.0));
              	t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_3 - sqrt(y))) + (t_1 - sqrt(z))) + t_2;
              	t_5 = sqrt((1.0 + x));
              	tmp = 0.0;
              	if (t_4 <= 1.0)
              		tmp = (t_5 - sqrt(x)) + t_2;
              	elseif (t_4 <= 2.0)
              		tmp = (t_5 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
              	else
              		tmp = ((((1.0 + (0.5 * x)) + t_3) + t_1) - sqrt(x)) - (sqrt(z) + sqrt(y));
              	end
              	tmp_2 = tmp;
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$4 = N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(t$95$3 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$1 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision]}, Block[{t$95$5 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$4, 1.0], N[(N[(t$95$5 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision], If[LessEqual[t$95$4, 2.0], N[(N[(t$95$5 + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(N[(1.0 + N[(0.5 * x), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[z], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \begin{array}{l}
              t_1 := \sqrt{z + 1}\\
              t_2 := \sqrt{t + 1} - \sqrt{t}\\
              t_3 := \sqrt{y + 1}\\
              t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_3 - \sqrt{y}\right)\right) + \left(t\_1 - \sqrt{z}\right)\right) + t\_2\\
              t_5 := \sqrt{1 + x}\\
              \mathbf{if}\;t\_4 \leq 1:\\
              \;\;\;\;\left(t\_5 - \sqrt{x}\right) + t\_2\\
              
              \mathbf{elif}\;t\_4 \leq 2:\\
              \;\;\;\;\left(t\_5 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(\left(\left(\left(1 + 0.5 \cdot x\right) + t\_3\right) + t\_1\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 3 regimes
              2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1

                1. Initial program 78.6%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in z around inf

                  \[\leadsto \color{blue}{\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. lower--.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  4. lower-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  5. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  6. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  7. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  8. lower-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  9. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  10. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  11. lift-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  12. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  13. lift-sqrt.f6413.1

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                4. Applied rewrites13.1%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                5. Taylor expanded in y around inf

                  \[\leadsto \left(\sqrt{1 + x} - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                6. Step-by-step derivation
                  1. lower--.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. lift-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. lift-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  4. lift-sqrt.f6478.4

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                7. Applied rewrites78.4%

                  \[\leadsto \left(\sqrt{1 + x} - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                if 1 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2

                1. Initial program 96.5%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in t around inf

                  \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites11.9%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                5. Taylor expanded in z around inf

                  \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                6. Step-by-step derivation
                  1. lower--.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \color{blue}{\sqrt{y}}\right) \]
                  2. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{\color{blue}{y}}\right) \]
                  3. lift-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  4. lift-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  5. lower-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  6. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  7. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  8. lift-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  9. lift-sqrt.f6496.0

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                7. Applied rewrites96.0%

                  \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]

                if 2 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

                1. Initial program 97.3%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in t around inf

                  \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites81.1%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                5. Taylor expanded in x around 0

                  \[\leadsto \left(\left(\left(\left(1 + \frac{1}{2} \cdot x\right) + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
                6. Step-by-step derivation
                  1. lower-+.f64N/A

                    \[\leadsto \left(\left(\left(\left(1 + \frac{1}{2} \cdot x\right) + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
                  2. lower-*.f6481.1

                    \[\leadsto \left(\left(\left(\left(1 + 0.5 \cdot x\right) + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
                7. Applied rewrites81.1%

                  \[\leadsto \left(\left(\left(\left(1 + 0.5 \cdot x\right) + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
              3. Recombined 3 regimes into one program.
              4. Add Preprocessing

              Alternative 7: 85.7% accurate, 0.4× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ t_3 := \sqrt{y + 1}\\ t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_3 - \sqrt{y}\right)\right) + \left(t\_1 - \sqrt{z}\right)\right) + t\_2\\ t_5 := \sqrt{1 + x}\\ \mathbf{if}\;t\_4 \leq 1:\\ \;\;\;\;\left(t\_5 - \sqrt{x}\right) + t\_2\\ \mathbf{elif}\;t\_4 \leq 2:\\ \;\;\;\;\left(t\_5 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(t\_5 + t\_3\right) + t\_1\right) - \sqrt{x}\right) - \sqrt{z}\\ \end{array} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t)
               :precision binary64
               (let* ((t_1 (sqrt (+ z 1.0)))
                      (t_2 (- (sqrt (+ t 1.0)) (sqrt t)))
                      (t_3 (sqrt (+ y 1.0)))
                      (t_4
                       (+
                        (+
                         (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- t_3 (sqrt y)))
                         (- t_1 (sqrt z)))
                        t_2))
                      (t_5 (sqrt (+ 1.0 x))))
                 (if (<= t_4 1.0)
                   (+ (- t_5 (sqrt x)) t_2)
                   (if (<= t_4 2.0)
                     (- (+ t_5 (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                     (- (- (+ (+ t_5 t_3) t_1) (sqrt x)) (sqrt z))))))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	double t_1 = sqrt((z + 1.0));
              	double t_2 = sqrt((t + 1.0)) - sqrt(t);
              	double t_3 = sqrt((y + 1.0));
              	double t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_3 - sqrt(y))) + (t_1 - sqrt(z))) + t_2;
              	double t_5 = sqrt((1.0 + x));
              	double tmp;
              	if (t_4 <= 1.0) {
              		tmp = (t_5 - sqrt(x)) + t_2;
              	} else if (t_4 <= 2.0) {
              		tmp = (t_5 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
              	} else {
              		tmp = (((t_5 + t_3) + t_1) - sqrt(x)) - sqrt(z);
              	}
              	return tmp;
              }
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(x, y, z, t)
              use fmin_fmax_functions
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  real(8) :: t_1
                  real(8) :: t_2
                  real(8) :: t_3
                  real(8) :: t_4
                  real(8) :: t_5
                  real(8) :: tmp
                  t_1 = sqrt((z + 1.0d0))
                  t_2 = sqrt((t + 1.0d0)) - sqrt(t)
                  t_3 = sqrt((y + 1.0d0))
                  t_4 = (((sqrt((x + 1.0d0)) - sqrt(x)) + (t_3 - sqrt(y))) + (t_1 - sqrt(z))) + t_2
                  t_5 = sqrt((1.0d0 + x))
                  if (t_4 <= 1.0d0) then
                      tmp = (t_5 - sqrt(x)) + t_2
                  else if (t_4 <= 2.0d0) then
                      tmp = (t_5 + sqrt((1.0d0 + y))) - (sqrt(x) + sqrt(y))
                  else
                      tmp = (((t_5 + t_3) + t_1) - sqrt(x)) - sqrt(z)
                  end if
                  code = tmp
              end function
              
              assert x < y && y < z && z < t;
              public static double code(double x, double y, double z, double t) {
              	double t_1 = Math.sqrt((z + 1.0));
              	double t_2 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
              	double t_3 = Math.sqrt((y + 1.0));
              	double t_4 = (((Math.sqrt((x + 1.0)) - Math.sqrt(x)) + (t_3 - Math.sqrt(y))) + (t_1 - Math.sqrt(z))) + t_2;
              	double t_5 = Math.sqrt((1.0 + x));
              	double tmp;
              	if (t_4 <= 1.0) {
              		tmp = (t_5 - Math.sqrt(x)) + t_2;
              	} else if (t_4 <= 2.0) {
              		tmp = (t_5 + Math.sqrt((1.0 + y))) - (Math.sqrt(x) + Math.sqrt(y));
              	} else {
              		tmp = (((t_5 + t_3) + t_1) - Math.sqrt(x)) - Math.sqrt(z);
              	}
              	return tmp;
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	t_1 = math.sqrt((z + 1.0))
              	t_2 = math.sqrt((t + 1.0)) - math.sqrt(t)
              	t_3 = math.sqrt((y + 1.0))
              	t_4 = (((math.sqrt((x + 1.0)) - math.sqrt(x)) + (t_3 - math.sqrt(y))) + (t_1 - math.sqrt(z))) + t_2
              	t_5 = math.sqrt((1.0 + x))
              	tmp = 0
              	if t_4 <= 1.0:
              		tmp = (t_5 - math.sqrt(x)) + t_2
              	elif t_4 <= 2.0:
              		tmp = (t_5 + math.sqrt((1.0 + y))) - (math.sqrt(x) + math.sqrt(y))
              	else:
              		tmp = (((t_5 + t_3) + t_1) - math.sqrt(x)) - math.sqrt(z)
              	return tmp
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	t_1 = sqrt(Float64(z + 1.0))
              	t_2 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
              	t_3 = sqrt(Float64(y + 1.0))
              	t_4 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(t_3 - sqrt(y))) + Float64(t_1 - sqrt(z))) + t_2)
              	t_5 = sqrt(Float64(1.0 + x))
              	tmp = 0.0
              	if (t_4 <= 1.0)
              		tmp = Float64(Float64(t_5 - sqrt(x)) + t_2);
              	elseif (t_4 <= 2.0)
              		tmp = Float64(Float64(t_5 + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
              	else
              		tmp = Float64(Float64(Float64(Float64(t_5 + t_3) + t_1) - sqrt(x)) - sqrt(z));
              	end
              	return tmp
              end
              
              x, y, z, t = num2cell(sort([x, y, z, t])){:}
              function tmp_2 = code(x, y, z, t)
              	t_1 = sqrt((z + 1.0));
              	t_2 = sqrt((t + 1.0)) - sqrt(t);
              	t_3 = sqrt((y + 1.0));
              	t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_3 - sqrt(y))) + (t_1 - sqrt(z))) + t_2;
              	t_5 = sqrt((1.0 + x));
              	tmp = 0.0;
              	if (t_4 <= 1.0)
              		tmp = (t_5 - sqrt(x)) + t_2;
              	elseif (t_4 <= 2.0)
              		tmp = (t_5 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
              	else
              		tmp = (((t_5 + t_3) + t_1) - sqrt(x)) - sqrt(z);
              	end
              	tmp_2 = tmp;
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$4 = N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(t$95$3 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$1 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision]}, Block[{t$95$5 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$4, 1.0], N[(N[(t$95$5 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision], If[LessEqual[t$95$4, 2.0], N[(N[(t$95$5 + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(t$95$5 + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]]]]]]]]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \begin{array}{l}
              t_1 := \sqrt{z + 1}\\
              t_2 := \sqrt{t + 1} - \sqrt{t}\\
              t_3 := \sqrt{y + 1}\\
              t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_3 - \sqrt{y}\right)\right) + \left(t\_1 - \sqrt{z}\right)\right) + t\_2\\
              t_5 := \sqrt{1 + x}\\
              \mathbf{if}\;t\_4 \leq 1:\\
              \;\;\;\;\left(t\_5 - \sqrt{x}\right) + t\_2\\
              
              \mathbf{elif}\;t\_4 \leq 2:\\
              \;\;\;\;\left(t\_5 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(\left(\left(t\_5 + t\_3\right) + t\_1\right) - \sqrt{x}\right) - \sqrt{z}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 3 regimes
              2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1

                1. Initial program 78.6%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in z around inf

                  \[\leadsto \color{blue}{\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. lower--.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  4. lower-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  5. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  6. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  7. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  8. lower-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  9. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  10. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  11. lift-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  12. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  13. lift-sqrt.f6413.1

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                4. Applied rewrites13.1%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                5. Taylor expanded in y around inf

                  \[\leadsto \left(\sqrt{1 + x} - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                6. Step-by-step derivation
                  1. lower--.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. lift-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. lift-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  4. lift-sqrt.f6478.4

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                7. Applied rewrites78.4%

                  \[\leadsto \left(\sqrt{1 + x} - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                if 1 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2

                1. Initial program 96.5%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in t around inf

                  \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites11.9%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                5. Taylor expanded in z around inf

                  \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                6. Step-by-step derivation
                  1. lower--.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \color{blue}{\sqrt{y}}\right) \]
                  2. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{\color{blue}{y}}\right) \]
                  3. lift-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  4. lift-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  5. lower-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  6. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  7. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  8. lift-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  9. lift-sqrt.f6496.0

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                7. Applied rewrites96.0%

                  \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]

                if 2 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

                1. Initial program 97.3%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in t around inf

                  \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites81.1%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                5. Taylor expanded in z around inf

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z} \]
                6. Step-by-step derivation
                  1. lift-sqrt.f6480.3

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z} \]
                7. Applied rewrites80.3%

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z} \]
              3. Recombined 3 regimes into one program.
              4. Add Preprocessing

              Alternative 8: 82.0% accurate, 0.4× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{1 + x}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ t_3 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + t\_2\\ t_4 := t\_1 + \sqrt{1 + y}\\ \mathbf{if}\;t\_3 \leq 1:\\ \;\;\;\;\left(t\_1 - \sqrt{x}\right) + t\_2\\ \mathbf{elif}\;t\_3 \leq 2.5:\\ \;\;\;\;t\_4 - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(1 + t\_4\right) - \sqrt{x}\right) - \sqrt{y}\\ \end{array} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t)
               :precision binary64
               (let* ((t_1 (sqrt (+ 1.0 x)))
                      (t_2 (- (sqrt (+ t 1.0)) (sqrt t)))
                      (t_3
                       (+
                        (+
                         (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
                         (- (sqrt (+ z 1.0)) (sqrt z)))
                        t_2))
                      (t_4 (+ t_1 (sqrt (+ 1.0 y)))))
                 (if (<= t_3 1.0)
                   (+ (- t_1 (sqrt x)) t_2)
                   (if (<= t_3 2.5)
                     (- t_4 (+ (sqrt x) (sqrt y)))
                     (- (- (+ 1.0 t_4) (sqrt x)) (sqrt y))))))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	double t_1 = sqrt((1.0 + x));
              	double t_2 = sqrt((t + 1.0)) - sqrt(t);
              	double t_3 = (((sqrt((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + t_2;
              	double t_4 = t_1 + sqrt((1.0 + y));
              	double tmp;
              	if (t_3 <= 1.0) {
              		tmp = (t_1 - sqrt(x)) + t_2;
              	} else if (t_3 <= 2.5) {
              		tmp = t_4 - (sqrt(x) + sqrt(y));
              	} else {
              		tmp = ((1.0 + t_4) - sqrt(x)) - sqrt(y);
              	}
              	return tmp;
              }
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(x, y, z, t)
              use fmin_fmax_functions
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  real(8) :: t_1
                  real(8) :: t_2
                  real(8) :: t_3
                  real(8) :: t_4
                  real(8) :: tmp
                  t_1 = sqrt((1.0d0 + x))
                  t_2 = sqrt((t + 1.0d0)) - sqrt(t)
                  t_3 = (((sqrt((x + 1.0d0)) - sqrt(x)) + (sqrt((y + 1.0d0)) - sqrt(y))) + (sqrt((z + 1.0d0)) - sqrt(z))) + t_2
                  t_4 = t_1 + sqrt((1.0d0 + y))
                  if (t_3 <= 1.0d0) then
                      tmp = (t_1 - sqrt(x)) + t_2
                  else if (t_3 <= 2.5d0) then
                      tmp = t_4 - (sqrt(x) + sqrt(y))
                  else
                      tmp = ((1.0d0 + t_4) - sqrt(x)) - sqrt(y)
                  end if
                  code = tmp
              end function
              
              assert x < y && y < z && z < t;
              public static double code(double x, double y, double z, double t) {
              	double t_1 = Math.sqrt((1.0 + x));
              	double t_2 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
              	double t_3 = (((Math.sqrt((x + 1.0)) - Math.sqrt(x)) + (Math.sqrt((y + 1.0)) - Math.sqrt(y))) + (Math.sqrt((z + 1.0)) - Math.sqrt(z))) + t_2;
              	double t_4 = t_1 + Math.sqrt((1.0 + y));
              	double tmp;
              	if (t_3 <= 1.0) {
              		tmp = (t_1 - Math.sqrt(x)) + t_2;
              	} else if (t_3 <= 2.5) {
              		tmp = t_4 - (Math.sqrt(x) + Math.sqrt(y));
              	} else {
              		tmp = ((1.0 + t_4) - Math.sqrt(x)) - Math.sqrt(y);
              	}
              	return tmp;
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	t_1 = math.sqrt((1.0 + x))
              	t_2 = math.sqrt((t + 1.0)) - math.sqrt(t)
              	t_3 = (((math.sqrt((x + 1.0)) - math.sqrt(x)) + (math.sqrt((y + 1.0)) - math.sqrt(y))) + (math.sqrt((z + 1.0)) - math.sqrt(z))) + t_2
              	t_4 = t_1 + math.sqrt((1.0 + y))
              	tmp = 0
              	if t_3 <= 1.0:
              		tmp = (t_1 - math.sqrt(x)) + t_2
              	elif t_3 <= 2.5:
              		tmp = t_4 - (math.sqrt(x) + math.sqrt(y))
              	else:
              		tmp = ((1.0 + t_4) - math.sqrt(x)) - math.sqrt(y)
              	return tmp
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	t_1 = sqrt(Float64(1.0 + x))
              	t_2 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
              	t_3 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(sqrt(Float64(y + 1.0)) - sqrt(y))) + Float64(sqrt(Float64(z + 1.0)) - sqrt(z))) + t_2)
              	t_4 = Float64(t_1 + sqrt(Float64(1.0 + y)))
              	tmp = 0.0
              	if (t_3 <= 1.0)
              		tmp = Float64(Float64(t_1 - sqrt(x)) + t_2);
              	elseif (t_3 <= 2.5)
              		tmp = Float64(t_4 - Float64(sqrt(x) + sqrt(y)));
              	else
              		tmp = Float64(Float64(Float64(1.0 + t_4) - sqrt(x)) - sqrt(y));
              	end
              	return tmp
              end
              
              x, y, z, t = num2cell(sort([x, y, z, t])){:}
              function tmp_2 = code(x, y, z, t)
              	t_1 = sqrt((1.0 + x));
              	t_2 = sqrt((t + 1.0)) - sqrt(t);
              	t_3 = (((sqrt((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + t_2;
              	t_4 = t_1 + sqrt((1.0 + y));
              	tmp = 0.0;
              	if (t_3 <= 1.0)
              		tmp = (t_1 - sqrt(x)) + t_2;
              	elseif (t_3 <= 2.5)
              		tmp = t_4 - (sqrt(x) + sqrt(y));
              	else
              		tmp = ((1.0 + t_4) - sqrt(x)) - sqrt(y);
              	end
              	tmp_2 = tmp;
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision]}, Block[{t$95$4 = N[(t$95$1 + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$3, 1.0], N[(N[(t$95$1 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision], If[LessEqual[t$95$3, 2.5], N[(t$95$4 - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(1.0 + t$95$4), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]]]]]]]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \begin{array}{l}
              t_1 := \sqrt{1 + x}\\
              t_2 := \sqrt{t + 1} - \sqrt{t}\\
              t_3 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + t\_2\\
              t_4 := t\_1 + \sqrt{1 + y}\\
              \mathbf{if}\;t\_3 \leq 1:\\
              \;\;\;\;\left(t\_1 - \sqrt{x}\right) + t\_2\\
              
              \mathbf{elif}\;t\_3 \leq 2.5:\\
              \;\;\;\;t\_4 - \left(\sqrt{x} + \sqrt{y}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(\left(1 + t\_4\right) - \sqrt{x}\right) - \sqrt{y}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 3 regimes
              2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1

                1. Initial program 78.6%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in z around inf

                  \[\leadsto \color{blue}{\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. lower--.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  4. lower-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  5. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  6. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  7. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  8. lower-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  9. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  10. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  11. lift-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  12. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  13. lift-sqrt.f6413.1

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                4. Applied rewrites13.1%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                5. Taylor expanded in y around inf

                  \[\leadsto \left(\sqrt{1 + x} - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                6. Step-by-step derivation
                  1. lower--.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. lift-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. lift-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  4. lift-sqrt.f6478.4

                    \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                7. Applied rewrites78.4%

                  \[\leadsto \left(\sqrt{1 + x} - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                if 1 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2.5

                1. Initial program 95.5%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in t around inf

                  \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites18.0%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                5. Taylor expanded in z around inf

                  \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                6. Step-by-step derivation
                  1. lower--.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \color{blue}{\sqrt{y}}\right) \]
                  2. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{\color{blue}{y}}\right) \]
                  3. lift-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  4. lift-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  5. lower-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  6. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  7. lower-+.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  8. lift-sqrt.f64N/A

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  9. lift-sqrt.f6491.3

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                7. Applied rewrites91.3%

                  \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]

                if 2.5 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

                1. Initial program 98.6%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Taylor expanded in t around inf

                  \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                3. Step-by-step derivation
                  1. associate--r+N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                  2. lower--.f64N/A

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites80.7%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                5. Taylor expanded in y around inf

                  \[\leadsto \sqrt{y} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                6. Step-by-step derivation
                  1. lift-sqrt.f641.7

                    \[\leadsto \sqrt{y} - \left(\sqrt{z} + \sqrt{y}\right) \]
                7. Applied rewrites1.7%

                  \[\leadsto \sqrt{y} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                8. Taylor expanded in y around inf

                  \[\leadsto \sqrt{y} - \sqrt{y} \]
                9. Step-by-step derivation
                  1. lift-sqrt.f643.1

                    \[\leadsto \sqrt{y} - \sqrt{y} \]
                10. Applied rewrites3.1%

                  \[\leadsto \sqrt{y} - \sqrt{y} \]
                11. Taylor expanded in z around 0

                  \[\leadsto \left(\left(1 + \left(\sqrt{1 + x} + \sqrt{1 + y}\right)\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}} \]
                12. Step-by-step derivation
                  1. lower--.f64N/A

                    \[\leadsto \left(\left(1 + \left(\sqrt{1 + x} + \sqrt{1 + y}\right)\right) - \sqrt{x}\right) - \sqrt{y} \]
                  2. lower-+.f64N/A

                    \[\leadsto \left(\left(1 + \left(\sqrt{1 + x} + \sqrt{1 + y}\right)\right) - \sqrt{x}\right) - \sqrt{y} \]
                  3. lower-+.f64N/A

                    \[\leadsto \left(\left(1 + \left(\sqrt{1 + x} + \sqrt{1 + y}\right)\right) - \sqrt{x}\right) - \sqrt{y} \]
                  4. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(1 + \left(\sqrt{1 + x} + \sqrt{1 + y}\right)\right) - \sqrt{x}\right) - \sqrt{y} \]
                  5. lift-+.f64N/A

                    \[\leadsto \left(\left(1 + \left(\sqrt{1 + x} + \sqrt{1 + y}\right)\right) - \sqrt{x}\right) - \sqrt{y} \]
                  6. lower-sqrt.f64N/A

                    \[\leadsto \left(\left(1 + \left(\sqrt{1 + x} + \sqrt{1 + y}\right)\right) - \sqrt{x}\right) - \sqrt{y} \]
                  7. lower-+.f64N/A

                    \[\leadsto \left(\left(1 + \left(\sqrt{1 + x} + \sqrt{1 + y}\right)\right) - \sqrt{x}\right) - \sqrt{y} \]
                  8. lift-sqrt.f6472.7

                    \[\leadsto \left(\left(1 + \left(\sqrt{1 + x} + \sqrt{1 + y}\right)\right) - \sqrt{x}\right) - \sqrt{y} \]
                13. Applied rewrites72.7%

                  \[\leadsto \left(\left(1 + \left(\sqrt{1 + x} + \sqrt{1 + y}\right)\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}} \]
              3. Recombined 3 regimes into one program.
              4. Add Preprocessing

              Alternative 9: 97.2% accurate, 0.5× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{z + 1} - \sqrt{z}\\ t_3 := t\_1 - \sqrt{y}\\ t_4 := \sqrt{x + 1} - \sqrt{x}\\ t_5 := \sqrt{t + 1} - \sqrt{t}\\ \mathbf{if}\;\left(\left(t\_4 + t\_3\right) + t\_2\right) + t\_5 \leq 0.4:\\ \;\;\;\;\left(\left(\frac{1}{\sqrt{1 + x} + \sqrt{x}} + t\_3\right) + t\_2\right) + t\_5\\ \mathbf{else}:\\ \;\;\;\;\left(\left(t\_4 + \frac{1}{t\_1 + \sqrt{y}}\right) + t\_2\right) + t\_5\\ \end{array} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t)
               :precision binary64
               (let* ((t_1 (sqrt (+ y 1.0)))
                      (t_2 (- (sqrt (+ z 1.0)) (sqrt z)))
                      (t_3 (- t_1 (sqrt y)))
                      (t_4 (- (sqrt (+ x 1.0)) (sqrt x)))
                      (t_5 (- (sqrt (+ t 1.0)) (sqrt t))))
                 (if (<= (+ (+ (+ t_4 t_3) t_2) t_5) 0.4)
                   (+ (+ (+ (/ 1.0 (+ (sqrt (+ 1.0 x)) (sqrt x))) t_3) t_2) t_5)
                   (+ (+ (+ t_4 (/ 1.0 (+ t_1 (sqrt y)))) t_2) t_5))))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	double t_1 = sqrt((y + 1.0));
              	double t_2 = sqrt((z + 1.0)) - sqrt(z);
              	double t_3 = t_1 - sqrt(y);
              	double t_4 = sqrt((x + 1.0)) - sqrt(x);
              	double t_5 = sqrt((t + 1.0)) - sqrt(t);
              	double tmp;
              	if ((((t_4 + t_3) + t_2) + t_5) <= 0.4) {
              		tmp = (((1.0 / (sqrt((1.0 + x)) + sqrt(x))) + t_3) + t_2) + t_5;
              	} else {
              		tmp = ((t_4 + (1.0 / (t_1 + sqrt(y)))) + t_2) + t_5;
              	}
              	return tmp;
              }
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(x, y, z, t)
              use fmin_fmax_functions
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  real(8) :: t_1
                  real(8) :: t_2
                  real(8) :: t_3
                  real(8) :: t_4
                  real(8) :: t_5
                  real(8) :: tmp
                  t_1 = sqrt((y + 1.0d0))
                  t_2 = sqrt((z + 1.0d0)) - sqrt(z)
                  t_3 = t_1 - sqrt(y)
                  t_4 = sqrt((x + 1.0d0)) - sqrt(x)
                  t_5 = sqrt((t + 1.0d0)) - sqrt(t)
                  if ((((t_4 + t_3) + t_2) + t_5) <= 0.4d0) then
                      tmp = (((1.0d0 / (sqrt((1.0d0 + x)) + sqrt(x))) + t_3) + t_2) + t_5
                  else
                      tmp = ((t_4 + (1.0d0 / (t_1 + sqrt(y)))) + t_2) + t_5
                  end if
                  code = tmp
              end function
              
              assert x < y && y < z && z < t;
              public static double code(double x, double y, double z, double t) {
              	double t_1 = Math.sqrt((y + 1.0));
              	double t_2 = Math.sqrt((z + 1.0)) - Math.sqrt(z);
              	double t_3 = t_1 - Math.sqrt(y);
              	double t_4 = Math.sqrt((x + 1.0)) - Math.sqrt(x);
              	double t_5 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
              	double tmp;
              	if ((((t_4 + t_3) + t_2) + t_5) <= 0.4) {
              		tmp = (((1.0 / (Math.sqrt((1.0 + x)) + Math.sqrt(x))) + t_3) + t_2) + t_5;
              	} else {
              		tmp = ((t_4 + (1.0 / (t_1 + Math.sqrt(y)))) + t_2) + t_5;
              	}
              	return tmp;
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	t_1 = math.sqrt((y + 1.0))
              	t_2 = math.sqrt((z + 1.0)) - math.sqrt(z)
              	t_3 = t_1 - math.sqrt(y)
              	t_4 = math.sqrt((x + 1.0)) - math.sqrt(x)
              	t_5 = math.sqrt((t + 1.0)) - math.sqrt(t)
              	tmp = 0
              	if (((t_4 + t_3) + t_2) + t_5) <= 0.4:
              		tmp = (((1.0 / (math.sqrt((1.0 + x)) + math.sqrt(x))) + t_3) + t_2) + t_5
              	else:
              		tmp = ((t_4 + (1.0 / (t_1 + math.sqrt(y)))) + t_2) + t_5
              	return tmp
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	t_1 = sqrt(Float64(y + 1.0))
              	t_2 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
              	t_3 = Float64(t_1 - sqrt(y))
              	t_4 = Float64(sqrt(Float64(x + 1.0)) - sqrt(x))
              	t_5 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
              	tmp = 0.0
              	if (Float64(Float64(Float64(t_4 + t_3) + t_2) + t_5) <= 0.4)
              		tmp = Float64(Float64(Float64(Float64(1.0 / Float64(sqrt(Float64(1.0 + x)) + sqrt(x))) + t_3) + t_2) + t_5);
              	else
              		tmp = Float64(Float64(Float64(t_4 + Float64(1.0 / Float64(t_1 + sqrt(y)))) + t_2) + t_5);
              	end
              	return tmp
              end
              
              x, y, z, t = num2cell(sort([x, y, z, t])){:}
              function tmp_2 = code(x, y, z, t)
              	t_1 = sqrt((y + 1.0));
              	t_2 = sqrt((z + 1.0)) - sqrt(z);
              	t_3 = t_1 - sqrt(y);
              	t_4 = sqrt((x + 1.0)) - sqrt(x);
              	t_5 = sqrt((t + 1.0)) - sqrt(t);
              	tmp = 0.0;
              	if ((((t_4 + t_3) + t_2) + t_5) <= 0.4)
              		tmp = (((1.0 / (sqrt((1.0 + x)) + sqrt(x))) + t_3) + t_2) + t_5;
              	else
              		tmp = ((t_4 + (1.0 / (t_1 + sqrt(y)))) + t_2) + t_5;
              	end
              	tmp_2 = tmp;
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(t$95$1 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(t$95$4 + t$95$3), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$5), $MachinePrecision], 0.4], N[(N[(N[(N[(1.0 / N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$5), $MachinePrecision], N[(N[(N[(t$95$4 + N[(1.0 / N[(t$95$1 + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$5), $MachinePrecision]]]]]]]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \begin{array}{l}
              t_1 := \sqrt{y + 1}\\
              t_2 := \sqrt{z + 1} - \sqrt{z}\\
              t_3 := t\_1 - \sqrt{y}\\
              t_4 := \sqrt{x + 1} - \sqrt{x}\\
              t_5 := \sqrt{t + 1} - \sqrt{t}\\
              \mathbf{if}\;\left(\left(t\_4 + t\_3\right) + t\_2\right) + t\_5 \leq 0.4:\\
              \;\;\;\;\left(\left(\frac{1}{\sqrt{1 + x} + \sqrt{x}} + t\_3\right) + t\_2\right) + t\_5\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(\left(t\_4 + \frac{1}{t\_1 + \sqrt{y}}\right) + t\_2\right) + t\_5\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 0.40000000000000002

                1. Initial program 15.6%

                  \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. Step-by-step derivation
                  1. lift--.f64N/A

                    \[\leadsto \left(\left(\color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right)} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. lift-+.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{\color{blue}{x + 1}} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\color{blue}{\sqrt{x + 1}} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  4. lift-sqrt.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  5. +-commutativeN/A

                    \[\leadsto \left(\left(\left(\sqrt{\color{blue}{1 + x}} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  6. flip--N/A

                    \[\leadsto \left(\left(\color{blue}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{1 + x} + \sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  7. lower-/.f64N/A

                    \[\leadsto \left(\left(\color{blue}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{1 + x} + \sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                3. Applied rewrites17.4%

                  \[\leadsto \left(\left(\color{blue}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{1 + x} + \sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                4. Taylor expanded in x around 0

                  \[\leadsto \left(\left(\frac{\color{blue}{1}}{\sqrt{1 + x} + \sqrt{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                5. Step-by-step derivation
                  1. Applied rewrites83.9%

                    \[\leadsto \left(\left(\frac{\color{blue}{1}}{\sqrt{1 + x} + \sqrt{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                  if 0.40000000000000002 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

                  1. Initial program 96.9%

                    \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. Step-by-step derivation
                    1. lift--.f64N/A

                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    2. lift-+.f64N/A

                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    3. lift-sqrt.f64N/A

                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    4. lift-sqrt.f64N/A

                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    5. +-commutativeN/A

                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    6. flip--N/A

                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    7. lower-/.f64N/A

                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. Applied rewrites97.1%

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  4. Taylor expanded in y around 0

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  5. Step-by-step derivation
                    1. Applied rewrites98.1%

                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  6. Recombined 2 regimes into one program.
                  7. Add Preprocessing

                  Alternative 10: 97.9% accurate, 0.5× speedup?

                  \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{z + 1} - \sqrt{z}\\ t_3 := \frac{1}{t\_1 + \sqrt{y}}\\ t_4 := \sqrt{x + 1} - \sqrt{x}\\ t_5 := \sqrt{t + 1} - \sqrt{t}\\ \mathbf{if}\;\left(\left(t\_4 + \left(t\_1 - \sqrt{y}\right)\right) + t\_2\right) + t\_5 \leq 2 \cdot 10^{-5}:\\ \;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + t\_3\right) + t\_2\right) + t\_5\\ \mathbf{else}:\\ \;\;\;\;\left(\left(t\_4 + t\_3\right) + t\_2\right) + t\_5\\ \end{array} \end{array} \]
                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                  (FPCore (x y z t)
                   :precision binary64
                   (let* ((t_1 (sqrt (+ y 1.0)))
                          (t_2 (- (sqrt (+ z 1.0)) (sqrt z)))
                          (t_3 (/ 1.0 (+ t_1 (sqrt y))))
                          (t_4 (- (sqrt (+ x 1.0)) (sqrt x)))
                          (t_5 (- (sqrt (+ t 1.0)) (sqrt t))))
                     (if (<= (+ (+ (+ t_4 (- t_1 (sqrt y))) t_2) t_5) 2e-5)
                       (+ (+ (+ (* 0.5 (/ 1.0 (sqrt x))) t_3) t_2) t_5)
                       (+ (+ (+ t_4 t_3) t_2) t_5))))
                  assert(x < y && y < z && z < t);
                  double code(double x, double y, double z, double t) {
                  	double t_1 = sqrt((y + 1.0));
                  	double t_2 = sqrt((z + 1.0)) - sqrt(z);
                  	double t_3 = 1.0 / (t_1 + sqrt(y));
                  	double t_4 = sqrt((x + 1.0)) - sqrt(x);
                  	double t_5 = sqrt((t + 1.0)) - sqrt(t);
                  	double tmp;
                  	if ((((t_4 + (t_1 - sqrt(y))) + t_2) + t_5) <= 2e-5) {
                  		tmp = (((0.5 * (1.0 / sqrt(x))) + t_3) + t_2) + t_5;
                  	} else {
                  		tmp = ((t_4 + t_3) + t_2) + t_5;
                  	}
                  	return tmp;
                  }
                  
                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                  module fmin_fmax_functions
                      implicit none
                      private
                      public fmax
                      public fmin
                  
                      interface fmax
                          module procedure fmax88
                          module procedure fmax44
                          module procedure fmax84
                          module procedure fmax48
                      end interface
                      interface fmin
                          module procedure fmin88
                          module procedure fmin44
                          module procedure fmin84
                          module procedure fmin48
                      end interface
                  contains
                      real(8) function fmax88(x, y) result (res)
                          real(8), intent (in) :: x
                          real(8), intent (in) :: y
                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                      end function
                      real(4) function fmax44(x, y) result (res)
                          real(4), intent (in) :: x
                          real(4), intent (in) :: y
                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                      end function
                      real(8) function fmax84(x, y) result(res)
                          real(8), intent (in) :: x
                          real(4), intent (in) :: y
                          res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                      end function
                      real(8) function fmax48(x, y) result(res)
                          real(4), intent (in) :: x
                          real(8), intent (in) :: y
                          res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                      end function
                      real(8) function fmin88(x, y) result (res)
                          real(8), intent (in) :: x
                          real(8), intent (in) :: y
                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                      end function
                      real(4) function fmin44(x, y) result (res)
                          real(4), intent (in) :: x
                          real(4), intent (in) :: y
                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                      end function
                      real(8) function fmin84(x, y) result(res)
                          real(8), intent (in) :: x
                          real(4), intent (in) :: y
                          res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                      end function
                      real(8) function fmin48(x, y) result(res)
                          real(4), intent (in) :: x
                          real(8), intent (in) :: y
                          res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                      end function
                  end module
                  
                  real(8) function code(x, y, z, t)
                  use fmin_fmax_functions
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      real(8), intent (in) :: z
                      real(8), intent (in) :: t
                      real(8) :: t_1
                      real(8) :: t_2
                      real(8) :: t_3
                      real(8) :: t_4
                      real(8) :: t_5
                      real(8) :: tmp
                      t_1 = sqrt((y + 1.0d0))
                      t_2 = sqrt((z + 1.0d0)) - sqrt(z)
                      t_3 = 1.0d0 / (t_1 + sqrt(y))
                      t_4 = sqrt((x + 1.0d0)) - sqrt(x)
                      t_5 = sqrt((t + 1.0d0)) - sqrt(t)
                      if ((((t_4 + (t_1 - sqrt(y))) + t_2) + t_5) <= 2d-5) then
                          tmp = (((0.5d0 * (1.0d0 / sqrt(x))) + t_3) + t_2) + t_5
                      else
                          tmp = ((t_4 + t_3) + t_2) + t_5
                      end if
                      code = tmp
                  end function
                  
                  assert x < y && y < z && z < t;
                  public static double code(double x, double y, double z, double t) {
                  	double t_1 = Math.sqrt((y + 1.0));
                  	double t_2 = Math.sqrt((z + 1.0)) - Math.sqrt(z);
                  	double t_3 = 1.0 / (t_1 + Math.sqrt(y));
                  	double t_4 = Math.sqrt((x + 1.0)) - Math.sqrt(x);
                  	double t_5 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
                  	double tmp;
                  	if ((((t_4 + (t_1 - Math.sqrt(y))) + t_2) + t_5) <= 2e-5) {
                  		tmp = (((0.5 * (1.0 / Math.sqrt(x))) + t_3) + t_2) + t_5;
                  	} else {
                  		tmp = ((t_4 + t_3) + t_2) + t_5;
                  	}
                  	return tmp;
                  }
                  
                  [x, y, z, t] = sort([x, y, z, t])
                  def code(x, y, z, t):
                  	t_1 = math.sqrt((y + 1.0))
                  	t_2 = math.sqrt((z + 1.0)) - math.sqrt(z)
                  	t_3 = 1.0 / (t_1 + math.sqrt(y))
                  	t_4 = math.sqrt((x + 1.0)) - math.sqrt(x)
                  	t_5 = math.sqrt((t + 1.0)) - math.sqrt(t)
                  	tmp = 0
                  	if (((t_4 + (t_1 - math.sqrt(y))) + t_2) + t_5) <= 2e-5:
                  		tmp = (((0.5 * (1.0 / math.sqrt(x))) + t_3) + t_2) + t_5
                  	else:
                  		tmp = ((t_4 + t_3) + t_2) + t_5
                  	return tmp
                  
                  x, y, z, t = sort([x, y, z, t])
                  function code(x, y, z, t)
                  	t_1 = sqrt(Float64(y + 1.0))
                  	t_2 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
                  	t_3 = Float64(1.0 / Float64(t_1 + sqrt(y)))
                  	t_4 = Float64(sqrt(Float64(x + 1.0)) - sqrt(x))
                  	t_5 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                  	tmp = 0.0
                  	if (Float64(Float64(Float64(t_4 + Float64(t_1 - sqrt(y))) + t_2) + t_5) <= 2e-5)
                  		tmp = Float64(Float64(Float64(Float64(0.5 * Float64(1.0 / sqrt(x))) + t_3) + t_2) + t_5);
                  	else
                  		tmp = Float64(Float64(Float64(t_4 + t_3) + t_2) + t_5);
                  	end
                  	return tmp
                  end
                  
                  x, y, z, t = num2cell(sort([x, y, z, t])){:}
                  function tmp_2 = code(x, y, z, t)
                  	t_1 = sqrt((y + 1.0));
                  	t_2 = sqrt((z + 1.0)) - sqrt(z);
                  	t_3 = 1.0 / (t_1 + sqrt(y));
                  	t_4 = sqrt((x + 1.0)) - sqrt(x);
                  	t_5 = sqrt((t + 1.0)) - sqrt(t);
                  	tmp = 0.0;
                  	if ((((t_4 + (t_1 - sqrt(y))) + t_2) + t_5) <= 2e-5)
                  		tmp = (((0.5 * (1.0 / sqrt(x))) + t_3) + t_2) + t_5;
                  	else
                  		tmp = ((t_4 + t_3) + t_2) + t_5;
                  	end
                  	tmp_2 = tmp;
                  end
                  
                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                  code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(1.0 / N[(t$95$1 + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(t$95$4 + N[(t$95$1 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$5), $MachinePrecision], 2e-5], N[(N[(N[(N[(0.5 * N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$5), $MachinePrecision], N[(N[(N[(t$95$4 + t$95$3), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$5), $MachinePrecision]]]]]]]
                  
                  \begin{array}{l}
                  [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                  \\
                  \begin{array}{l}
                  t_1 := \sqrt{y + 1}\\
                  t_2 := \sqrt{z + 1} - \sqrt{z}\\
                  t_3 := \frac{1}{t\_1 + \sqrt{y}}\\
                  t_4 := \sqrt{x + 1} - \sqrt{x}\\
                  t_5 := \sqrt{t + 1} - \sqrt{t}\\
                  \mathbf{if}\;\left(\left(t\_4 + \left(t\_1 - \sqrt{y}\right)\right) + t\_2\right) + t\_5 \leq 2 \cdot 10^{-5}:\\
                  \;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + t\_3\right) + t\_2\right) + t\_5\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;\left(\left(t\_4 + t\_3\right) + t\_2\right) + t\_5\\
                  
                  
                  \end{array}
                  \end{array}
                  
                  Derivation
                  1. Split input into 2 regimes
                  2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2.00000000000000016e-5

                    1. Initial program 7.4%

                      \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    2. Step-by-step derivation
                      1. lift--.f64N/A

                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      2. lift-+.f64N/A

                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      3. lift-sqrt.f64N/A

                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      4. lift-sqrt.f64N/A

                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      5. +-commutativeN/A

                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      6. flip--N/A

                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      7. lower-/.f64N/A

                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    3. Applied rewrites7.4%

                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    4. Taylor expanded in y around 0

                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    5. Step-by-step derivation
                      1. Applied rewrites12.9%

                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      2. Taylor expanded in x around inf

                        \[\leadsto \left(\left(\color{blue}{\frac{1}{2} \cdot \sqrt{\frac{1}{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      3. Step-by-step derivation
                        1. lower-*.f64N/A

                          \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\sqrt{\frac{1}{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        2. sqrt-divN/A

                          \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{\sqrt{1}}{\color{blue}{\sqrt{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        3. metadata-evalN/A

                          \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{1}{\sqrt{\color{blue}{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        4. lower-/.f64N/A

                          \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        5. lift-sqrt.f6495.9

                          \[\leadsto \left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      4. Applied rewrites95.9%

                        \[\leadsto \left(\left(\color{blue}{0.5 \cdot \frac{1}{\sqrt{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                      if 2.00000000000000016e-5 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

                      1. Initial program 96.7%

                        \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      2. Step-by-step derivation
                        1. lift--.f64N/A

                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        2. lift-+.f64N/A

                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        3. lift-sqrt.f64N/A

                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        4. lift-sqrt.f64N/A

                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        5. +-commutativeN/A

                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        6. flip--N/A

                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        7. lower-/.f64N/A

                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      3. Applied rewrites96.9%

                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      4. Taylor expanded in y around 0

                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      5. Step-by-step derivation
                        1. Applied rewrites98.0%

                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      6. Recombined 2 regimes into one program.
                      7. Add Preprocessing

                      Alternative 11: 97.2% accurate, 0.5× speedup?

                      \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{z + 1} - \sqrt{z}\\ t_3 := \frac{1}{t\_1 + \sqrt{y}}\\ t_4 := \sqrt{t + 1} - \sqrt{t}\\ \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + t\_2\right) + t\_4 \leq 0.4:\\ \;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + t\_3\right) + t\_2\right) + t\_4\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + t\_2\right) + t\_4\\ \end{array} \end{array} \]
                      NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                      (FPCore (x y z t)
                       :precision binary64
                       (let* ((t_1 (sqrt (+ y 1.0)))
                              (t_2 (- (sqrt (+ z 1.0)) (sqrt z)))
                              (t_3 (/ 1.0 (+ t_1 (sqrt y))))
                              (t_4 (- (sqrt (+ t 1.0)) (sqrt t))))
                         (if (<=
                              (+ (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- t_1 (sqrt y))) t_2) t_4)
                              0.4)
                           (+ (+ (+ (* 0.5 (/ 1.0 (sqrt x))) t_3) t_2) t_4)
                           (+ (+ (+ (- 1.0 (sqrt x)) t_3) t_2) t_4))))
                      assert(x < y && y < z && z < t);
                      double code(double x, double y, double z, double t) {
                      	double t_1 = sqrt((y + 1.0));
                      	double t_2 = sqrt((z + 1.0)) - sqrt(z);
                      	double t_3 = 1.0 / (t_1 + sqrt(y));
                      	double t_4 = sqrt((t + 1.0)) - sqrt(t);
                      	double tmp;
                      	if (((((sqrt((x + 1.0)) - sqrt(x)) + (t_1 - sqrt(y))) + t_2) + t_4) <= 0.4) {
                      		tmp = (((0.5 * (1.0 / sqrt(x))) + t_3) + t_2) + t_4;
                      	} else {
                      		tmp = (((1.0 - sqrt(x)) + t_3) + t_2) + t_4;
                      	}
                      	return tmp;
                      }
                      
                      NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                      module fmin_fmax_functions
                          implicit none
                          private
                          public fmax
                          public fmin
                      
                          interface fmax
                              module procedure fmax88
                              module procedure fmax44
                              module procedure fmax84
                              module procedure fmax48
                          end interface
                          interface fmin
                              module procedure fmin88
                              module procedure fmin44
                              module procedure fmin84
                              module procedure fmin48
                          end interface
                      contains
                          real(8) function fmax88(x, y) result (res)
                              real(8), intent (in) :: x
                              real(8), intent (in) :: y
                              res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                          end function
                          real(4) function fmax44(x, y) result (res)
                              real(4), intent (in) :: x
                              real(4), intent (in) :: y
                              res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                          end function
                          real(8) function fmax84(x, y) result(res)
                              real(8), intent (in) :: x
                              real(4), intent (in) :: y
                              res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                          end function
                          real(8) function fmax48(x, y) result(res)
                              real(4), intent (in) :: x
                              real(8), intent (in) :: y
                              res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                          end function
                          real(8) function fmin88(x, y) result (res)
                              real(8), intent (in) :: x
                              real(8), intent (in) :: y
                              res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                          end function
                          real(4) function fmin44(x, y) result (res)
                              real(4), intent (in) :: x
                              real(4), intent (in) :: y
                              res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                          end function
                          real(8) function fmin84(x, y) result(res)
                              real(8), intent (in) :: x
                              real(4), intent (in) :: y
                              res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                          end function
                          real(8) function fmin48(x, y) result(res)
                              real(4), intent (in) :: x
                              real(8), intent (in) :: y
                              res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                          end function
                      end module
                      
                      real(8) function code(x, y, z, t)
                      use fmin_fmax_functions
                          real(8), intent (in) :: x
                          real(8), intent (in) :: y
                          real(8), intent (in) :: z
                          real(8), intent (in) :: t
                          real(8) :: t_1
                          real(8) :: t_2
                          real(8) :: t_3
                          real(8) :: t_4
                          real(8) :: tmp
                          t_1 = sqrt((y + 1.0d0))
                          t_2 = sqrt((z + 1.0d0)) - sqrt(z)
                          t_3 = 1.0d0 / (t_1 + sqrt(y))
                          t_4 = sqrt((t + 1.0d0)) - sqrt(t)
                          if (((((sqrt((x + 1.0d0)) - sqrt(x)) + (t_1 - sqrt(y))) + t_2) + t_4) <= 0.4d0) then
                              tmp = (((0.5d0 * (1.0d0 / sqrt(x))) + t_3) + t_2) + t_4
                          else
                              tmp = (((1.0d0 - sqrt(x)) + t_3) + t_2) + t_4
                          end if
                          code = tmp
                      end function
                      
                      assert x < y && y < z && z < t;
                      public static double code(double x, double y, double z, double t) {
                      	double t_1 = Math.sqrt((y + 1.0));
                      	double t_2 = Math.sqrt((z + 1.0)) - Math.sqrt(z);
                      	double t_3 = 1.0 / (t_1 + Math.sqrt(y));
                      	double t_4 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
                      	double tmp;
                      	if (((((Math.sqrt((x + 1.0)) - Math.sqrt(x)) + (t_1 - Math.sqrt(y))) + t_2) + t_4) <= 0.4) {
                      		tmp = (((0.5 * (1.0 / Math.sqrt(x))) + t_3) + t_2) + t_4;
                      	} else {
                      		tmp = (((1.0 - Math.sqrt(x)) + t_3) + t_2) + t_4;
                      	}
                      	return tmp;
                      }
                      
                      [x, y, z, t] = sort([x, y, z, t])
                      def code(x, y, z, t):
                      	t_1 = math.sqrt((y + 1.0))
                      	t_2 = math.sqrt((z + 1.0)) - math.sqrt(z)
                      	t_3 = 1.0 / (t_1 + math.sqrt(y))
                      	t_4 = math.sqrt((t + 1.0)) - math.sqrt(t)
                      	tmp = 0
                      	if ((((math.sqrt((x + 1.0)) - math.sqrt(x)) + (t_1 - math.sqrt(y))) + t_2) + t_4) <= 0.4:
                      		tmp = (((0.5 * (1.0 / math.sqrt(x))) + t_3) + t_2) + t_4
                      	else:
                      		tmp = (((1.0 - math.sqrt(x)) + t_3) + t_2) + t_4
                      	return tmp
                      
                      x, y, z, t = sort([x, y, z, t])
                      function code(x, y, z, t)
                      	t_1 = sqrt(Float64(y + 1.0))
                      	t_2 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
                      	t_3 = Float64(1.0 / Float64(t_1 + sqrt(y)))
                      	t_4 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                      	tmp = 0.0
                      	if (Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(t_1 - sqrt(y))) + t_2) + t_4) <= 0.4)
                      		tmp = Float64(Float64(Float64(Float64(0.5 * Float64(1.0 / sqrt(x))) + t_3) + t_2) + t_4);
                      	else
                      		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + t_3) + t_2) + t_4);
                      	end
                      	return tmp
                      end
                      
                      x, y, z, t = num2cell(sort([x, y, z, t])){:}
                      function tmp_2 = code(x, y, z, t)
                      	t_1 = sqrt((y + 1.0));
                      	t_2 = sqrt((z + 1.0)) - sqrt(z);
                      	t_3 = 1.0 / (t_1 + sqrt(y));
                      	t_4 = sqrt((t + 1.0)) - sqrt(t);
                      	tmp = 0.0;
                      	if (((((sqrt((x + 1.0)) - sqrt(x)) + (t_1 - sqrt(y))) + t_2) + t_4) <= 0.4)
                      		tmp = (((0.5 * (1.0 / sqrt(x))) + t_3) + t_2) + t_4;
                      	else
                      		tmp = (((1.0 - sqrt(x)) + t_3) + t_2) + t_4;
                      	end
                      	tmp_2 = tmp;
                      end
                      
                      NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                      code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(1.0 / N[(t$95$1 + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(t$95$1 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$4), $MachinePrecision], 0.4], N[(N[(N[(N[(0.5 * N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$4), $MachinePrecision], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$4), $MachinePrecision]]]]]]
                      
                      \begin{array}{l}
                      [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                      \\
                      \begin{array}{l}
                      t_1 := \sqrt{y + 1}\\
                      t_2 := \sqrt{z + 1} - \sqrt{z}\\
                      t_3 := \frac{1}{t\_1 + \sqrt{y}}\\
                      t_4 := \sqrt{t + 1} - \sqrt{t}\\
                      \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + t\_2\right) + t\_4 \leq 0.4:\\
                      \;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + t\_3\right) + t\_2\right) + t\_4\\
                      
                      \mathbf{else}:\\
                      \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + t\_2\right) + t\_4\\
                      
                      
                      \end{array}
                      \end{array}
                      
                      Derivation
                      1. Split input into 2 regimes
                      2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 0.40000000000000002

                        1. Initial program 15.6%

                          \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        2. Step-by-step derivation
                          1. lift--.f64N/A

                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          2. lift-+.f64N/A

                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          3. lift-sqrt.f64N/A

                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          4. lift-sqrt.f64N/A

                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          5. +-commutativeN/A

                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          6. flip--N/A

                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          7. lower-/.f64N/A

                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        3. Applied rewrites15.8%

                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        4. Taylor expanded in y around 0

                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        5. Step-by-step derivation
                          1. Applied rewrites21.0%

                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          2. Taylor expanded in x around inf

                            \[\leadsto \left(\left(\color{blue}{\frac{1}{2} \cdot \sqrt{\frac{1}{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          3. Step-by-step derivation
                            1. lower-*.f64N/A

                              \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\sqrt{\frac{1}{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            2. sqrt-divN/A

                              \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{\sqrt{1}}{\color{blue}{\sqrt{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            3. metadata-evalN/A

                              \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{1}{\sqrt{\color{blue}{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            4. lower-/.f64N/A

                              \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            5. lift-sqrt.f6489.4

                              \[\leadsto \left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          4. Applied rewrites89.4%

                            \[\leadsto \left(\left(\color{blue}{0.5 \cdot \frac{1}{\sqrt{x}}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                          if 0.40000000000000002 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

                          1. Initial program 96.9%

                            \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          2. Step-by-step derivation
                            1. lift--.f64N/A

                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            2. lift-+.f64N/A

                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            3. lift-sqrt.f64N/A

                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            4. lift-sqrt.f64N/A

                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            5. +-commutativeN/A

                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            6. flip--N/A

                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            7. lower-/.f64N/A

                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          3. Applied rewrites97.1%

                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          4. Taylor expanded in y around 0

                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          5. Step-by-step derivation
                            1. Applied rewrites98.1%

                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            2. Taylor expanded in x around 0

                              \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            3. Step-by-step derivation
                              1. Applied rewrites97.7%

                                \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            4. Recombined 2 regimes into one program.
                            5. Add Preprocessing

                            Alternative 12: 96.4% accurate, 0.5× speedup?

                            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{z + 1} - \sqrt{z}\\ t_3 := \sqrt{t + 1} - \sqrt{t}\\ t_4 := t\_1 - \sqrt{y}\\ \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_4\right) + t\_2\right) + t\_3 \leq 0.4:\\ \;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + t\_4\right) + t\_2\right) + t\_3\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + \frac{1}{t\_1 + \sqrt{y}}\right) + t\_2\right) + t\_3\\ \end{array} \end{array} \]
                            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                            (FPCore (x y z t)
                             :precision binary64
                             (let* ((t_1 (sqrt (+ y 1.0)))
                                    (t_2 (- (sqrt (+ z 1.0)) (sqrt z)))
                                    (t_3 (- (sqrt (+ t 1.0)) (sqrt t)))
                                    (t_4 (- t_1 (sqrt y))))
                               (if (<= (+ (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) t_4) t_2) t_3) 0.4)
                                 (+ (+ (+ (* 0.5 (/ 1.0 (sqrt x))) t_4) t_2) t_3)
                                 (+ (+ (+ (- 1.0 (sqrt x)) (/ 1.0 (+ t_1 (sqrt y)))) t_2) t_3))))
                            assert(x < y && y < z && z < t);
                            double code(double x, double y, double z, double t) {
                            	double t_1 = sqrt((y + 1.0));
                            	double t_2 = sqrt((z + 1.0)) - sqrt(z);
                            	double t_3 = sqrt((t + 1.0)) - sqrt(t);
                            	double t_4 = t_1 - sqrt(y);
                            	double tmp;
                            	if (((((sqrt((x + 1.0)) - sqrt(x)) + t_4) + t_2) + t_3) <= 0.4) {
                            		tmp = (((0.5 * (1.0 / sqrt(x))) + t_4) + t_2) + t_3;
                            	} else {
                            		tmp = (((1.0 - sqrt(x)) + (1.0 / (t_1 + sqrt(y)))) + t_2) + t_3;
                            	}
                            	return tmp;
                            }
                            
                            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                            module fmin_fmax_functions
                                implicit none
                                private
                                public fmax
                                public fmin
                            
                                interface fmax
                                    module procedure fmax88
                                    module procedure fmax44
                                    module procedure fmax84
                                    module procedure fmax48
                                end interface
                                interface fmin
                                    module procedure fmin88
                                    module procedure fmin44
                                    module procedure fmin84
                                    module procedure fmin48
                                end interface
                            contains
                                real(8) function fmax88(x, y) result (res)
                                    real(8), intent (in) :: x
                                    real(8), intent (in) :: y
                                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                end function
                                real(4) function fmax44(x, y) result (res)
                                    real(4), intent (in) :: x
                                    real(4), intent (in) :: y
                                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                end function
                                real(8) function fmax84(x, y) result(res)
                                    real(8), intent (in) :: x
                                    real(4), intent (in) :: y
                                    res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                end function
                                real(8) function fmax48(x, y) result(res)
                                    real(4), intent (in) :: x
                                    real(8), intent (in) :: y
                                    res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                end function
                                real(8) function fmin88(x, y) result (res)
                                    real(8), intent (in) :: x
                                    real(8), intent (in) :: y
                                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                end function
                                real(4) function fmin44(x, y) result (res)
                                    real(4), intent (in) :: x
                                    real(4), intent (in) :: y
                                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                end function
                                real(8) function fmin84(x, y) result(res)
                                    real(8), intent (in) :: x
                                    real(4), intent (in) :: y
                                    res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                end function
                                real(8) function fmin48(x, y) result(res)
                                    real(4), intent (in) :: x
                                    real(8), intent (in) :: y
                                    res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                end function
                            end module
                            
                            real(8) function code(x, y, z, t)
                            use fmin_fmax_functions
                                real(8), intent (in) :: x
                                real(8), intent (in) :: y
                                real(8), intent (in) :: z
                                real(8), intent (in) :: t
                                real(8) :: t_1
                                real(8) :: t_2
                                real(8) :: t_3
                                real(8) :: t_4
                                real(8) :: tmp
                                t_1 = sqrt((y + 1.0d0))
                                t_2 = sqrt((z + 1.0d0)) - sqrt(z)
                                t_3 = sqrt((t + 1.0d0)) - sqrt(t)
                                t_4 = t_1 - sqrt(y)
                                if (((((sqrt((x + 1.0d0)) - sqrt(x)) + t_4) + t_2) + t_3) <= 0.4d0) then
                                    tmp = (((0.5d0 * (1.0d0 / sqrt(x))) + t_4) + t_2) + t_3
                                else
                                    tmp = (((1.0d0 - sqrt(x)) + (1.0d0 / (t_1 + sqrt(y)))) + t_2) + t_3
                                end if
                                code = tmp
                            end function
                            
                            assert x < y && y < z && z < t;
                            public static double code(double x, double y, double z, double t) {
                            	double t_1 = Math.sqrt((y + 1.0));
                            	double t_2 = Math.sqrt((z + 1.0)) - Math.sqrt(z);
                            	double t_3 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
                            	double t_4 = t_1 - Math.sqrt(y);
                            	double tmp;
                            	if (((((Math.sqrt((x + 1.0)) - Math.sqrt(x)) + t_4) + t_2) + t_3) <= 0.4) {
                            		tmp = (((0.5 * (1.0 / Math.sqrt(x))) + t_4) + t_2) + t_3;
                            	} else {
                            		tmp = (((1.0 - Math.sqrt(x)) + (1.0 / (t_1 + Math.sqrt(y)))) + t_2) + t_3;
                            	}
                            	return tmp;
                            }
                            
                            [x, y, z, t] = sort([x, y, z, t])
                            def code(x, y, z, t):
                            	t_1 = math.sqrt((y + 1.0))
                            	t_2 = math.sqrt((z + 1.0)) - math.sqrt(z)
                            	t_3 = math.sqrt((t + 1.0)) - math.sqrt(t)
                            	t_4 = t_1 - math.sqrt(y)
                            	tmp = 0
                            	if ((((math.sqrt((x + 1.0)) - math.sqrt(x)) + t_4) + t_2) + t_3) <= 0.4:
                            		tmp = (((0.5 * (1.0 / math.sqrt(x))) + t_4) + t_2) + t_3
                            	else:
                            		tmp = (((1.0 - math.sqrt(x)) + (1.0 / (t_1 + math.sqrt(y)))) + t_2) + t_3
                            	return tmp
                            
                            x, y, z, t = sort([x, y, z, t])
                            function code(x, y, z, t)
                            	t_1 = sqrt(Float64(y + 1.0))
                            	t_2 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
                            	t_3 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                            	t_4 = Float64(t_1 - sqrt(y))
                            	tmp = 0.0
                            	if (Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + t_4) + t_2) + t_3) <= 0.4)
                            		tmp = Float64(Float64(Float64(Float64(0.5 * Float64(1.0 / sqrt(x))) + t_4) + t_2) + t_3);
                            	else
                            		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + Float64(1.0 / Float64(t_1 + sqrt(y)))) + t_2) + t_3);
                            	end
                            	return tmp
                            end
                            
                            x, y, z, t = num2cell(sort([x, y, z, t])){:}
                            function tmp_2 = code(x, y, z, t)
                            	t_1 = sqrt((y + 1.0));
                            	t_2 = sqrt((z + 1.0)) - sqrt(z);
                            	t_3 = sqrt((t + 1.0)) - sqrt(t);
                            	t_4 = t_1 - sqrt(y);
                            	tmp = 0.0;
                            	if (((((sqrt((x + 1.0)) - sqrt(x)) + t_4) + t_2) + t_3) <= 0.4)
                            		tmp = (((0.5 * (1.0 / sqrt(x))) + t_4) + t_2) + t_3;
                            	else
                            		tmp = (((1.0 - sqrt(x)) + (1.0 / (t_1 + sqrt(y)))) + t_2) + t_3;
                            	end
                            	tmp_2 = tmp;
                            end
                            
                            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                            code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(t$95$1 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$4), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$3), $MachinePrecision], 0.4], N[(N[(N[(N[(0.5 * N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$4), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$3), $MachinePrecision], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(t$95$1 + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$3), $MachinePrecision]]]]]]
                            
                            \begin{array}{l}
                            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                            \\
                            \begin{array}{l}
                            t_1 := \sqrt{y + 1}\\
                            t_2 := \sqrt{z + 1} - \sqrt{z}\\
                            t_3 := \sqrt{t + 1} - \sqrt{t}\\
                            t_4 := t\_1 - \sqrt{y}\\
                            \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_4\right) + t\_2\right) + t\_3 \leq 0.4:\\
                            \;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + t\_4\right) + t\_2\right) + t\_3\\
                            
                            \mathbf{else}:\\
                            \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + \frac{1}{t\_1 + \sqrt{y}}\right) + t\_2\right) + t\_3\\
                            
                            
                            \end{array}
                            \end{array}
                            
                            Derivation
                            1. Split input into 2 regimes
                            2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 0.40000000000000002

                              1. Initial program 15.6%

                                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              2. Step-by-step derivation
                                1. lift--.f64N/A

                                  \[\leadsto \left(\left(\color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right)} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                2. lift-+.f64N/A

                                  \[\leadsto \left(\left(\left(\sqrt{\color{blue}{x + 1}} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                3. lift-sqrt.f64N/A

                                  \[\leadsto \left(\left(\left(\color{blue}{\sqrt{x + 1}} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                4. lift-sqrt.f64N/A

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                5. +-commutativeN/A

                                  \[\leadsto \left(\left(\left(\sqrt{\color{blue}{1 + x}} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                6. flip--N/A

                                  \[\leadsto \left(\left(\color{blue}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{1 + x} + \sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                7. lower-/.f64N/A

                                  \[\leadsto \left(\left(\color{blue}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{1 + x} + \sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              3. Applied rewrites17.4%

                                \[\leadsto \left(\left(\color{blue}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{1 + x} + \sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              4. Taylor expanded in x around inf

                                \[\leadsto \left(\left(\color{blue}{\frac{1}{2} \cdot \sqrt{\frac{1}{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              5. Step-by-step derivation
                                1. lower-*.f64N/A

                                  \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\sqrt{\frac{1}{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                2. sqrt-divN/A

                                  \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{\sqrt{1}}{\color{blue}{\sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                3. metadata-evalN/A

                                  \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{1}{\sqrt{\color{blue}{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                4. lower-/.f64N/A

                                  \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                5. lift-sqrt.f6477.0

                                  \[\leadsto \left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              6. Applied rewrites77.0%

                                \[\leadsto \left(\left(\color{blue}{0.5 \cdot \frac{1}{\sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                              if 0.40000000000000002 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

                              1. Initial program 96.9%

                                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              2. Step-by-step derivation
                                1. lift--.f64N/A

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                2. lift-+.f64N/A

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                3. lift-sqrt.f64N/A

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                4. lift-sqrt.f64N/A

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                5. +-commutativeN/A

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                6. flip--N/A

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                7. lower-/.f64N/A

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              3. Applied rewrites97.1%

                                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              4. Taylor expanded in y around 0

                                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              5. Step-by-step derivation
                                1. Applied rewrites98.1%

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                2. Taylor expanded in x around 0

                                  \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                3. Step-by-step derivation
                                  1. Applied rewrites97.7%

                                    \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                4. Recombined 2 regimes into one program.
                                5. Add Preprocessing

                                Alternative 13: 92.8% accurate, 0.5× speedup?

                                \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1} - \sqrt{z}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ t_3 := \sqrt{y + 1} - \sqrt{y}\\ \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2 \leq 1.0002:\\ \;\;\;\;\left(\left(\mathsf{fma}\left(\frac{1}{\sqrt{y}}, 0.5, \sqrt{1 + x}\right) - \sqrt{x}\right) + t\_1\right) + t\_2\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\ \end{array} \end{array} \]
                                NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                (FPCore (x y z t)
                                 :precision binary64
                                 (let* ((t_1 (- (sqrt (+ z 1.0)) (sqrt z)))
                                        (t_2 (- (sqrt (+ t 1.0)) (sqrt t)))
                                        (t_3 (- (sqrt (+ y 1.0)) (sqrt y))))
                                   (if (<= (+ (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) t_3) t_1) t_2) 1.0002)
                                     (+ (+ (- (fma (/ 1.0 (sqrt y)) 0.5 (sqrt (+ 1.0 x))) (sqrt x)) t_1) t_2)
                                     (+ (+ (+ (- (fma 0.5 x 1.0) (sqrt x)) t_3) t_1) t_2))))
                                assert(x < y && y < z && z < t);
                                double code(double x, double y, double z, double t) {
                                	double t_1 = sqrt((z + 1.0)) - sqrt(z);
                                	double t_2 = sqrt((t + 1.0)) - sqrt(t);
                                	double t_3 = sqrt((y + 1.0)) - sqrt(y);
                                	double tmp;
                                	if (((((sqrt((x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2) <= 1.0002) {
                                		tmp = ((fma((1.0 / sqrt(y)), 0.5, sqrt((1.0 + x))) - sqrt(x)) + t_1) + t_2;
                                	} else {
                                		tmp = (((fma(0.5, x, 1.0) - sqrt(x)) + t_3) + t_1) + t_2;
                                	}
                                	return tmp;
                                }
                                
                                x, y, z, t = sort([x, y, z, t])
                                function code(x, y, z, t)
                                	t_1 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
                                	t_2 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                                	t_3 = Float64(sqrt(Float64(y + 1.0)) - sqrt(y))
                                	tmp = 0.0
                                	if (Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2) <= 1.0002)
                                		tmp = Float64(Float64(Float64(fma(Float64(1.0 / sqrt(y)), 0.5, sqrt(Float64(1.0 + x))) - sqrt(x)) + t_1) + t_2);
                                	else
                                		tmp = Float64(Float64(Float64(Float64(fma(0.5, x, 1.0) - sqrt(x)) + t_3) + t_1) + t_2);
                                	end
                                	return tmp
                                end
                                
                                NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision], 1.0002], N[(N[(N[(N[(N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision] * 0.5 + N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision], N[(N[(N[(N[(N[(0.5 * x + 1.0), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision]]]]]
                                
                                \begin{array}{l}
                                [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                \\
                                \begin{array}{l}
                                t_1 := \sqrt{z + 1} - \sqrt{z}\\
                                t_2 := \sqrt{t + 1} - \sqrt{t}\\
                                t_3 := \sqrt{y + 1} - \sqrt{y}\\
                                \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2 \leq 1.0002:\\
                                \;\;\;\;\left(\left(\mathsf{fma}\left(\frac{1}{\sqrt{y}}, 0.5, \sqrt{1 + x}\right) - \sqrt{x}\right) + t\_1\right) + t\_2\\
                                
                                \mathbf{else}:\\
                                \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\
                                
                                
                                \end{array}
                                \end{array}
                                
                                Derivation
                                1. Split input into 2 regimes
                                2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.0002

                                  1. Initial program 78.4%

                                    \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  2. Taylor expanded in y around inf

                                    \[\leadsto \left(\color{blue}{\left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  3. Step-by-step derivation
                                    1. lower--.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    2. +-commutativeN/A

                                      \[\leadsto \left(\left(\left(\frac{1}{2} \cdot \sqrt{\frac{1}{y}} + \sqrt{1 + x}\right) - \sqrt{\color{blue}{x}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    3. *-commutativeN/A

                                      \[\leadsto \left(\left(\left(\sqrt{\frac{1}{y}} \cdot \frac{1}{2} + \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    4. lower-fma.f64N/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left(\sqrt{\frac{1}{y}}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{\color{blue}{x}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    5. sqrt-divN/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left(\frac{\sqrt{1}}{\sqrt{y}}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    6. metadata-evalN/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left(\frac{1}{\sqrt{y}}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    7. inv-powN/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    8. lower-pow.f64N/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    9. lift-sqrt.f64N/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    10. +-commutativeN/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{1}{2}, \sqrt{x + 1}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    11. lift-sqrt.f64N/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{1}{2}, \sqrt{x + 1}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    12. +-commutativeN/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    13. lower-+.f64N/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    14. lift-sqrt.f6481.8

                                      \[\leadsto \left(\left(\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, 0.5, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  4. Applied rewrites81.8%

                                    \[\leadsto \left(\color{blue}{\left(\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, 0.5, \sqrt{1 + x}\right) - \sqrt{x}\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  5. Step-by-step derivation
                                    1. lift-pow.f64N/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    2. lift-sqrt.f64N/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    3. unpow-1N/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left(\frac{1}{\sqrt{y}}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    4. lower-/.f64N/A

                                      \[\leadsto \left(\left(\mathsf{fma}\left(\frac{1}{\sqrt{y}}, \frac{1}{2}, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    5. lift-sqrt.f6481.8

                                      \[\leadsto \left(\left(\mathsf{fma}\left(\frac{1}{\sqrt{y}}, 0.5, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  6. Applied rewrites81.8%

                                    \[\leadsto \left(\left(\mathsf{fma}\left(\frac{1}{\sqrt{y}}, 0.5, \sqrt{1 + x}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                                  if 1.0002 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

                                  1. Initial program 97.5%

                                    \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  2. Taylor expanded in x around 0

                                    \[\leadsto \left(\left(\left(\color{blue}{\left(1 + \frac{1}{2} \cdot x\right)} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  3. Step-by-step derivation
                                    1. +-commutativeN/A

                                      \[\leadsto \left(\left(\left(\left(\frac{1}{2} \cdot x + \color{blue}{1}\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    2. lower-fma.f6497.5

                                      \[\leadsto \left(\left(\left(\mathsf{fma}\left(0.5, \color{blue}{x}, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  4. Applied rewrites97.5%

                                    \[\leadsto \left(\left(\left(\color{blue}{\mathsf{fma}\left(0.5, x, 1\right)} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                3. Recombined 2 regimes into one program.
                                4. Add Preprocessing

                                Alternative 14: 92.8% accurate, 0.5× speedup?

                                \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1} - \sqrt{z}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ t_3 := \sqrt{y + 1} - \sqrt{y}\\ \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2 \leq 1.0002:\\ \;\;\;\;\left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + t\_2\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\ \end{array} \end{array} \]
                                NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                (FPCore (x y z t)
                                 :precision binary64
                                 (let* ((t_1 (- (sqrt (+ z 1.0)) (sqrt z)))
                                        (t_2 (- (sqrt (+ t 1.0)) (sqrt t)))
                                        (t_3 (- (sqrt (+ y 1.0)) (sqrt y))))
                                   (if (<= (+ (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) t_3) t_1) t_2) 1.0002)
                                     (+ (- (+ (sqrt (+ 1.0 x)) (* 0.5 (/ 1.0 (sqrt y)))) (sqrt x)) t_2)
                                     (+ (+ (+ (- (fma 0.5 x 1.0) (sqrt x)) t_3) t_1) t_2))))
                                assert(x < y && y < z && z < t);
                                double code(double x, double y, double z, double t) {
                                	double t_1 = sqrt((z + 1.0)) - sqrt(z);
                                	double t_2 = sqrt((t + 1.0)) - sqrt(t);
                                	double t_3 = sqrt((y + 1.0)) - sqrt(y);
                                	double tmp;
                                	if (((((sqrt((x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2) <= 1.0002) {
                                		tmp = ((sqrt((1.0 + x)) + (0.5 * (1.0 / sqrt(y)))) - sqrt(x)) + t_2;
                                	} else {
                                		tmp = (((fma(0.5, x, 1.0) - sqrt(x)) + t_3) + t_1) + t_2;
                                	}
                                	return tmp;
                                }
                                
                                x, y, z, t = sort([x, y, z, t])
                                function code(x, y, z, t)
                                	t_1 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
                                	t_2 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                                	t_3 = Float64(sqrt(Float64(y + 1.0)) - sqrt(y))
                                	tmp = 0.0
                                	if (Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2) <= 1.0002)
                                		tmp = Float64(Float64(Float64(sqrt(Float64(1.0 + x)) + Float64(0.5 * Float64(1.0 / sqrt(y)))) - sqrt(x)) + t_2);
                                	else
                                		tmp = Float64(Float64(Float64(Float64(fma(0.5, x, 1.0) - sqrt(x)) + t_3) + t_1) + t_2);
                                	end
                                	return tmp
                                end
                                
                                NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision], 1.0002], N[(N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision], N[(N[(N[(N[(N[(0.5 * x + 1.0), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision]]]]]
                                
                                \begin{array}{l}
                                [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                \\
                                \begin{array}{l}
                                t_1 := \sqrt{z + 1} - \sqrt{z}\\
                                t_2 := \sqrt{t + 1} - \sqrt{t}\\
                                t_3 := \sqrt{y + 1} - \sqrt{y}\\
                                \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2 \leq 1.0002:\\
                                \;\;\;\;\left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + t\_2\\
                                
                                \mathbf{else}:\\
                                \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\
                                
                                
                                \end{array}
                                \end{array}
                                
                                Derivation
                                1. Split input into 2 regimes
                                2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.0002

                                  1. Initial program 78.4%

                                    \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  2. Taylor expanded in z around inf

                                    \[\leadsto \color{blue}{\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  3. Step-by-step derivation
                                    1. associate--r+N/A

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    2. lower--.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    3. lower--.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    4. lower-+.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    5. +-commutativeN/A

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    6. lift-sqrt.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    7. +-commutativeN/A

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    8. lower-+.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    9. +-commutativeN/A

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    10. lift-sqrt.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    11. lift-+.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    12. lift-sqrt.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    13. lift-sqrt.f6417.3

                                      \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  4. Applied rewrites17.3%

                                    \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  5. Taylor expanded in y around inf

                                    \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  6. Step-by-step derivation
                                    1. lower--.f64N/A

                                      \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    2. lower-+.f64N/A

                                      \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    3. lift-sqrt.f64N/A

                                      \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    4. lift-+.f64N/A

                                      \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    5. lower-*.f64N/A

                                      \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    6. sqrt-divN/A

                                      \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{\sqrt{1}}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    7. metadata-evalN/A

                                      \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    8. lower-/.f64N/A

                                      \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    9. lift-sqrt.f64N/A

                                      \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    10. lift-sqrt.f6481.7

                                      \[\leadsto \left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  7. Applied rewrites81.7%

                                    \[\leadsto \left(\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                                  if 1.0002 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

                                  1. Initial program 97.5%

                                    \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  2. Taylor expanded in x around 0

                                    \[\leadsto \left(\left(\left(\color{blue}{\left(1 + \frac{1}{2} \cdot x\right)} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  3. Step-by-step derivation
                                    1. +-commutativeN/A

                                      \[\leadsto \left(\left(\left(\left(\frac{1}{2} \cdot x + \color{blue}{1}\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    2. lower-fma.f6497.5

                                      \[\leadsto \left(\left(\left(\mathsf{fma}\left(0.5, \color{blue}{x}, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  4. Applied rewrites97.5%

                                    \[\leadsto \left(\left(\left(\color{blue}{\mathsf{fma}\left(0.5, x, 1\right)} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                3. Recombined 2 regimes into one program.
                                4. Add Preprocessing

                                Alternative 15: 98.0% accurate, 0.5× speedup?

                                \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{t + 1} - \sqrt{t}\\ \mathbf{if}\;x \leq 880000000:\\ \;\;\;\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + t\_1\\ \mathbf{else}:\\ \;\;\;\;\left(\mathsf{fma}\left(0.5, \frac{1}{\sqrt{x}}, {\left(\sqrt{y} + \sqrt{1 + y}\right)}^{-1}\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + t\_1\\ \end{array} \end{array} \]
                                NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                (FPCore (x y z t)
                                 :precision binary64
                                 (let* ((t_1 (- (sqrt (+ t 1.0)) (sqrt t))))
                                   (if (<= x 880000000.0)
                                     (+
                                      (+
                                       (+ (- (sqrt (+ x 1.0)) (sqrt x)) (/ 1.0 (+ (sqrt (+ y 1.0)) (sqrt y))))
                                       (- (sqrt (+ z 1.0)) (sqrt z)))
                                      t_1)
                                     (+
                                      (+
                                       (fma 0.5 (/ 1.0 (sqrt x)) (pow (+ (sqrt y) (sqrt (+ 1.0 y))) -1.0))
                                       (* 0.5 (/ 1.0 (sqrt z))))
                                      t_1))))
                                assert(x < y && y < z && z < t);
                                double code(double x, double y, double z, double t) {
                                	double t_1 = sqrt((t + 1.0)) - sqrt(t);
                                	double tmp;
                                	if (x <= 880000000.0) {
                                		tmp = (((sqrt((x + 1.0)) - sqrt(x)) + (1.0 / (sqrt((y + 1.0)) + sqrt(y)))) + (sqrt((z + 1.0)) - sqrt(z))) + t_1;
                                	} else {
                                		tmp = (fma(0.5, (1.0 / sqrt(x)), pow((sqrt(y) + sqrt((1.0 + y))), -1.0)) + (0.5 * (1.0 / sqrt(z)))) + t_1;
                                	}
                                	return tmp;
                                }
                                
                                x, y, z, t = sort([x, y, z, t])
                                function code(x, y, z, t)
                                	t_1 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                                	tmp = 0.0
                                	if (x <= 880000000.0)
                                		tmp = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(1.0 / Float64(sqrt(Float64(y + 1.0)) + sqrt(y)))) + Float64(sqrt(Float64(z + 1.0)) - sqrt(z))) + t_1);
                                	else
                                		tmp = Float64(Float64(fma(0.5, Float64(1.0 / sqrt(x)), (Float64(sqrt(y) + sqrt(Float64(1.0 + y))) ^ -1.0)) + Float64(0.5 * Float64(1.0 / sqrt(z)))) + t_1);
                                	end
                                	return tmp
                                end
                                
                                NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 880000000.0], N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision], N[(N[(N[(0.5 * N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[Power[N[(N[Sqrt[y], $MachinePrecision] + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], -1.0], $MachinePrecision]), $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision]]]
                                
                                \begin{array}{l}
                                [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                \\
                                \begin{array}{l}
                                t_1 := \sqrt{t + 1} - \sqrt{t}\\
                                \mathbf{if}\;x \leq 880000000:\\
                                \;\;\;\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + t\_1\\
                                
                                \mathbf{else}:\\
                                \;\;\;\;\left(\mathsf{fma}\left(0.5, \frac{1}{\sqrt{x}}, {\left(\sqrt{y} + \sqrt{1 + y}\right)}^{-1}\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + t\_1\\
                                
                                
                                \end{array}
                                \end{array}
                                
                                Derivation
                                1. Split input into 2 regimes
                                2. if x < 8.8e8

                                  1. Initial program 96.7%

                                    \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  2. Step-by-step derivation
                                    1. lift--.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    2. lift-+.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    3. lift-sqrt.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    4. lift-sqrt.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    5. +-commutativeN/A

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    6. flip--N/A

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    7. lower-/.f64N/A

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  3. Applied rewrites96.9%

                                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  4. Taylor expanded in y around 0

                                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  5. Step-by-step derivation
                                    1. Applied rewrites98.0%

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                                    if 8.8e8 < x

                                    1. Initial program 7.4%

                                      \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    2. Step-by-step derivation
                                      1. lift--.f64N/A

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      2. lift-+.f64N/A

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      3. lift-sqrt.f64N/A

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      4. lift-sqrt.f64N/A

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      5. +-commutativeN/A

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      6. flip--N/A

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      7. lower-/.f64N/A

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    3. Applied rewrites7.4%

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    4. Taylor expanded in y around 0

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    5. Step-by-step derivation
                                      1. Applied rewrites12.9%

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      2. Taylor expanded in z around inf

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \color{blue}{\frac{1}{2} \cdot \sqrt{\frac{1}{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      3. Step-by-step derivation
                                        1. lower-*.f64N/A

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \color{blue}{\sqrt{\frac{1}{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        2. sqrt-divN/A

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{\sqrt{1}}{\color{blue}{\sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        3. metadata-evalN/A

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{\color{blue}{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        4. lower-/.f64N/A

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        5. lift-sqrt.f6412.9

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      4. Applied rewrites12.9%

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \color{blue}{0.5 \cdot \frac{1}{\sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      5. Taylor expanded in x around inf

                                        \[\leadsto \left(\color{blue}{\left(\frac{1}{2} \cdot \sqrt{\frac{1}{x}} + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right)} + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      6. Step-by-step derivation
                                        1. lower-fma.f64N/A

                                          \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \color{blue}{\sqrt{\frac{1}{x}}}, \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        2. sqrt-divN/A

                                          \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \frac{\sqrt{1}}{\color{blue}{\sqrt{x}}}, \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        3. metadata-evalN/A

                                          \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \frac{1}{\sqrt{\color{blue}{x}}}, \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        4. lower-/.f64N/A

                                          \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \frac{1}{\color{blue}{\sqrt{x}}}, \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        5. lift-sqrt.f64N/A

                                          \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \frac{1}{\sqrt{x}}, \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        6. inv-powN/A

                                          \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \frac{1}{\sqrt{x}}, {\left(\sqrt{y} + \sqrt{1 + y}\right)}^{-1}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        7. lower-pow.f64N/A

                                          \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \frac{1}{\sqrt{x}}, {\left(\sqrt{y} + \sqrt{1 + y}\right)}^{-1}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        8. lower-+.f64N/A

                                          \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \frac{1}{\sqrt{x}}, {\left(\sqrt{y} + \sqrt{1 + y}\right)}^{-1}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        9. lift-sqrt.f64N/A

                                          \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \frac{1}{\sqrt{x}}, {\left(\sqrt{y} + \sqrt{1 + y}\right)}^{-1}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        10. lower-sqrt.f64N/A

                                          \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \frac{1}{\sqrt{x}}, {\left(\sqrt{y} + \sqrt{1 + y}\right)}^{-1}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        11. lower-+.f6497.7

                                          \[\leadsto \left(\mathsf{fma}\left(0.5, \frac{1}{\sqrt{x}}, {\left(\sqrt{y} + \sqrt{1 + y}\right)}^{-1}\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      7. Applied rewrites97.7%

                                        \[\leadsto \left(\color{blue}{\mathsf{fma}\left(0.5, \frac{1}{\sqrt{x}}, {\left(\sqrt{y} + \sqrt{1 + y}\right)}^{-1}\right)} + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    6. Recombined 2 regimes into one program.
                                    7. Add Preprocessing

                                    Alternative 16: 92.9% accurate, 1.0× speedup?

                                    \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1} - \sqrt{z}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ \mathbf{if}\;x \leq 4.8 \cdot 10^{-27}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + t\_1\right) + t\_2\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{1 + \sqrt{y}}\right) + t\_1\right) + t\_2\\ \end{array} \end{array} \]
                                    NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                    (FPCore (x y z t)
                                     :precision binary64
                                     (let* ((t_1 (- (sqrt (+ z 1.0)) (sqrt z)))
                                            (t_2 (- (sqrt (+ t 1.0)) (sqrt t))))
                                       (if (<= x 4.8e-27)
                                         (+ (+ (+ (- 1.0 (sqrt x)) (/ 1.0 (+ (sqrt (+ y 1.0)) (sqrt y)))) t_1) t_2)
                                         (+
                                          (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) (/ 1.0 (+ 1.0 (sqrt y)))) t_1)
                                          t_2))))
                                    assert(x < y && y < z && z < t);
                                    double code(double x, double y, double z, double t) {
                                    	double t_1 = sqrt((z + 1.0)) - sqrt(z);
                                    	double t_2 = sqrt((t + 1.0)) - sqrt(t);
                                    	double tmp;
                                    	if (x <= 4.8e-27) {
                                    		tmp = (((1.0 - sqrt(x)) + (1.0 / (sqrt((y + 1.0)) + sqrt(y)))) + t_1) + t_2;
                                    	} else {
                                    		tmp = (((sqrt((x + 1.0)) - sqrt(x)) + (1.0 / (1.0 + sqrt(y)))) + t_1) + t_2;
                                    	}
                                    	return tmp;
                                    }
                                    
                                    NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                    module fmin_fmax_functions
                                        implicit none
                                        private
                                        public fmax
                                        public fmin
                                    
                                        interface fmax
                                            module procedure fmax88
                                            module procedure fmax44
                                            module procedure fmax84
                                            module procedure fmax48
                                        end interface
                                        interface fmin
                                            module procedure fmin88
                                            module procedure fmin44
                                            module procedure fmin84
                                            module procedure fmin48
                                        end interface
                                    contains
                                        real(8) function fmax88(x, y) result (res)
                                            real(8), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                        end function
                                        real(4) function fmax44(x, y) result (res)
                                            real(4), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                        end function
                                        real(8) function fmax84(x, y) result(res)
                                            real(8), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                        end function
                                        real(8) function fmax48(x, y) result(res)
                                            real(4), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                        end function
                                        real(8) function fmin88(x, y) result (res)
                                            real(8), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                        end function
                                        real(4) function fmin44(x, y) result (res)
                                            real(4), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                        end function
                                        real(8) function fmin84(x, y) result(res)
                                            real(8), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                        end function
                                        real(8) function fmin48(x, y) result(res)
                                            real(4), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                        end function
                                    end module
                                    
                                    real(8) function code(x, y, z, t)
                                    use fmin_fmax_functions
                                        real(8), intent (in) :: x
                                        real(8), intent (in) :: y
                                        real(8), intent (in) :: z
                                        real(8), intent (in) :: t
                                        real(8) :: t_1
                                        real(8) :: t_2
                                        real(8) :: tmp
                                        t_1 = sqrt((z + 1.0d0)) - sqrt(z)
                                        t_2 = sqrt((t + 1.0d0)) - sqrt(t)
                                        if (x <= 4.8d-27) then
                                            tmp = (((1.0d0 - sqrt(x)) + (1.0d0 / (sqrt((y + 1.0d0)) + sqrt(y)))) + t_1) + t_2
                                        else
                                            tmp = (((sqrt((x + 1.0d0)) - sqrt(x)) + (1.0d0 / (1.0d0 + sqrt(y)))) + t_1) + t_2
                                        end if
                                        code = tmp
                                    end function
                                    
                                    assert x < y && y < z && z < t;
                                    public static double code(double x, double y, double z, double t) {
                                    	double t_1 = Math.sqrt((z + 1.0)) - Math.sqrt(z);
                                    	double t_2 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
                                    	double tmp;
                                    	if (x <= 4.8e-27) {
                                    		tmp = (((1.0 - Math.sqrt(x)) + (1.0 / (Math.sqrt((y + 1.0)) + Math.sqrt(y)))) + t_1) + t_2;
                                    	} else {
                                    		tmp = (((Math.sqrt((x + 1.0)) - Math.sqrt(x)) + (1.0 / (1.0 + Math.sqrt(y)))) + t_1) + t_2;
                                    	}
                                    	return tmp;
                                    }
                                    
                                    [x, y, z, t] = sort([x, y, z, t])
                                    def code(x, y, z, t):
                                    	t_1 = math.sqrt((z + 1.0)) - math.sqrt(z)
                                    	t_2 = math.sqrt((t + 1.0)) - math.sqrt(t)
                                    	tmp = 0
                                    	if x <= 4.8e-27:
                                    		tmp = (((1.0 - math.sqrt(x)) + (1.0 / (math.sqrt((y + 1.0)) + math.sqrt(y)))) + t_1) + t_2
                                    	else:
                                    		tmp = (((math.sqrt((x + 1.0)) - math.sqrt(x)) + (1.0 / (1.0 + math.sqrt(y)))) + t_1) + t_2
                                    	return tmp
                                    
                                    x, y, z, t = sort([x, y, z, t])
                                    function code(x, y, z, t)
                                    	t_1 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
                                    	t_2 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                                    	tmp = 0.0
                                    	if (x <= 4.8e-27)
                                    		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + Float64(1.0 / Float64(sqrt(Float64(y + 1.0)) + sqrt(y)))) + t_1) + t_2);
                                    	else
                                    		tmp = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(1.0 / Float64(1.0 + sqrt(y)))) + t_1) + t_2);
                                    	end
                                    	return tmp
                                    end
                                    
                                    x, y, z, t = num2cell(sort([x, y, z, t])){:}
                                    function tmp_2 = code(x, y, z, t)
                                    	t_1 = sqrt((z + 1.0)) - sqrt(z);
                                    	t_2 = sqrt((t + 1.0)) - sqrt(t);
                                    	tmp = 0.0;
                                    	if (x <= 4.8e-27)
                                    		tmp = (((1.0 - sqrt(x)) + (1.0 / (sqrt((y + 1.0)) + sqrt(y)))) + t_1) + t_2;
                                    	else
                                    		tmp = (((sqrt((x + 1.0)) - sqrt(x)) + (1.0 / (1.0 + sqrt(y)))) + t_1) + t_2;
                                    	end
                                    	tmp_2 = tmp;
                                    end
                                    
                                    NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                    code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 4.8e-27], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision], N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(1.0 + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision]]]]
                                    
                                    \begin{array}{l}
                                    [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                    \\
                                    \begin{array}{l}
                                    t_1 := \sqrt{z + 1} - \sqrt{z}\\
                                    t_2 := \sqrt{t + 1} - \sqrt{t}\\
                                    \mathbf{if}\;x \leq 4.8 \cdot 10^{-27}:\\
                                    \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + t\_1\right) + t\_2\\
                                    
                                    \mathbf{else}:\\
                                    \;\;\;\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{1 + \sqrt{y}}\right) + t\_1\right) + t\_2\\
                                    
                                    
                                    \end{array}
                                    \end{array}
                                    
                                    Derivation
                                    1. Split input into 2 regimes
                                    2. if x < 4.80000000000000004e-27

                                      1. Initial program 96.9%

                                        \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      2. Step-by-step derivation
                                        1. lift--.f64N/A

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        2. lift-+.f64N/A

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        3. lift-sqrt.f64N/A

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        4. lift-sqrt.f64N/A

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        5. +-commutativeN/A

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        6. flip--N/A

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        7. lower-/.f64N/A

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      3. Applied rewrites97.1%

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      4. Taylor expanded in y around 0

                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                      5. Step-by-step derivation
                                        1. Applied rewrites98.1%

                                          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        2. Taylor expanded in x around 0

                                          \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        3. Step-by-step derivation
                                          1. Applied rewrites98.1%

                                            \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                                          if 4.80000000000000004e-27 < x

                                          1. Initial program 36.3%

                                            \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                          2. Step-by-step derivation
                                            1. lift--.f64N/A

                                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            2. lift-+.f64N/A

                                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            3. lift-sqrt.f64N/A

                                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            4. lift-sqrt.f64N/A

                                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            5. +-commutativeN/A

                                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            6. flip--N/A

                                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            7. lower-/.f64N/A

                                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                          3. Applied rewrites36.6%

                                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                          4. Taylor expanded in y around 0

                                            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                          5. Step-by-step derivation
                                            1. Applied rewrites41.3%

                                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            2. Taylor expanded in y around 0

                                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\color{blue}{1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            3. Step-by-step derivation
                                              1. Applied rewrites36.6%

                                                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\color{blue}{1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            4. Recombined 2 regimes into one program.
                                            5. Add Preprocessing

                                            Alternative 17: 92.8% accurate, 1.0× speedup?

                                            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{t + 1} - \sqrt{t}\\ \mathbf{if}\;x \leq 1.7 \cdot 10^{-24}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + t\_1\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\sqrt{1 + x} - \sqrt{x}\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + t\_1\\ \end{array} \end{array} \]
                                            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                            (FPCore (x y z t)
                                             :precision binary64
                                             (let* ((t_1 (- (sqrt (+ t 1.0)) (sqrt t))))
                                               (if (<= x 1.7e-24)
                                                 (+
                                                  (+
                                                   (+ (- 1.0 (sqrt x)) (/ 1.0 (+ (sqrt (+ y 1.0)) (sqrt y))))
                                                   (- (sqrt (+ z 1.0)) (sqrt z)))
                                                  t_1)
                                                 (+ (+ (- (sqrt (+ 1.0 x)) (sqrt x)) (* 0.5 (/ 1.0 (sqrt z)))) t_1))))
                                            assert(x < y && y < z && z < t);
                                            double code(double x, double y, double z, double t) {
                                            	double t_1 = sqrt((t + 1.0)) - sqrt(t);
                                            	double tmp;
                                            	if (x <= 1.7e-24) {
                                            		tmp = (((1.0 - sqrt(x)) + (1.0 / (sqrt((y + 1.0)) + sqrt(y)))) + (sqrt((z + 1.0)) - sqrt(z))) + t_1;
                                            	} else {
                                            		tmp = ((sqrt((1.0 + x)) - sqrt(x)) + (0.5 * (1.0 / sqrt(z)))) + t_1;
                                            	}
                                            	return tmp;
                                            }
                                            
                                            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                            module fmin_fmax_functions
                                                implicit none
                                                private
                                                public fmax
                                                public fmin
                                            
                                                interface fmax
                                                    module procedure fmax88
                                                    module procedure fmax44
                                                    module procedure fmax84
                                                    module procedure fmax48
                                                end interface
                                                interface fmin
                                                    module procedure fmin88
                                                    module procedure fmin44
                                                    module procedure fmin84
                                                    module procedure fmin48
                                                end interface
                                            contains
                                                real(8) function fmax88(x, y) result (res)
                                                    real(8), intent (in) :: x
                                                    real(8), intent (in) :: y
                                                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                end function
                                                real(4) function fmax44(x, y) result (res)
                                                    real(4), intent (in) :: x
                                                    real(4), intent (in) :: y
                                                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                end function
                                                real(8) function fmax84(x, y) result(res)
                                                    real(8), intent (in) :: x
                                                    real(4), intent (in) :: y
                                                    res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                                end function
                                                real(8) function fmax48(x, y) result(res)
                                                    real(4), intent (in) :: x
                                                    real(8), intent (in) :: y
                                                    res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                                end function
                                                real(8) function fmin88(x, y) result (res)
                                                    real(8), intent (in) :: x
                                                    real(8), intent (in) :: y
                                                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                end function
                                                real(4) function fmin44(x, y) result (res)
                                                    real(4), intent (in) :: x
                                                    real(4), intent (in) :: y
                                                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                end function
                                                real(8) function fmin84(x, y) result(res)
                                                    real(8), intent (in) :: x
                                                    real(4), intent (in) :: y
                                                    res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                                end function
                                                real(8) function fmin48(x, y) result(res)
                                                    real(4), intent (in) :: x
                                                    real(8), intent (in) :: y
                                                    res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                                end function
                                            end module
                                            
                                            real(8) function code(x, y, z, t)
                                            use fmin_fmax_functions
                                                real(8), intent (in) :: x
                                                real(8), intent (in) :: y
                                                real(8), intent (in) :: z
                                                real(8), intent (in) :: t
                                                real(8) :: t_1
                                                real(8) :: tmp
                                                t_1 = sqrt((t + 1.0d0)) - sqrt(t)
                                                if (x <= 1.7d-24) then
                                                    tmp = (((1.0d0 - sqrt(x)) + (1.0d0 / (sqrt((y + 1.0d0)) + sqrt(y)))) + (sqrt((z + 1.0d0)) - sqrt(z))) + t_1
                                                else
                                                    tmp = ((sqrt((1.0d0 + x)) - sqrt(x)) + (0.5d0 * (1.0d0 / sqrt(z)))) + t_1
                                                end if
                                                code = tmp
                                            end function
                                            
                                            assert x < y && y < z && z < t;
                                            public static double code(double x, double y, double z, double t) {
                                            	double t_1 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
                                            	double tmp;
                                            	if (x <= 1.7e-24) {
                                            		tmp = (((1.0 - Math.sqrt(x)) + (1.0 / (Math.sqrt((y + 1.0)) + Math.sqrt(y)))) + (Math.sqrt((z + 1.0)) - Math.sqrt(z))) + t_1;
                                            	} else {
                                            		tmp = ((Math.sqrt((1.0 + x)) - Math.sqrt(x)) + (0.5 * (1.0 / Math.sqrt(z)))) + t_1;
                                            	}
                                            	return tmp;
                                            }
                                            
                                            [x, y, z, t] = sort([x, y, z, t])
                                            def code(x, y, z, t):
                                            	t_1 = math.sqrt((t + 1.0)) - math.sqrt(t)
                                            	tmp = 0
                                            	if x <= 1.7e-24:
                                            		tmp = (((1.0 - math.sqrt(x)) + (1.0 / (math.sqrt((y + 1.0)) + math.sqrt(y)))) + (math.sqrt((z + 1.0)) - math.sqrt(z))) + t_1
                                            	else:
                                            		tmp = ((math.sqrt((1.0 + x)) - math.sqrt(x)) + (0.5 * (1.0 / math.sqrt(z)))) + t_1
                                            	return tmp
                                            
                                            x, y, z, t = sort([x, y, z, t])
                                            function code(x, y, z, t)
                                            	t_1 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                                            	tmp = 0.0
                                            	if (x <= 1.7e-24)
                                            		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + Float64(1.0 / Float64(sqrt(Float64(y + 1.0)) + sqrt(y)))) + Float64(sqrt(Float64(z + 1.0)) - sqrt(z))) + t_1);
                                            	else
                                            		tmp = Float64(Float64(Float64(sqrt(Float64(1.0 + x)) - sqrt(x)) + Float64(0.5 * Float64(1.0 / sqrt(z)))) + t_1);
                                            	end
                                            	return tmp
                                            end
                                            
                                            x, y, z, t = num2cell(sort([x, y, z, t])){:}
                                            function tmp_2 = code(x, y, z, t)
                                            	t_1 = sqrt((t + 1.0)) - sqrt(t);
                                            	tmp = 0.0;
                                            	if (x <= 1.7e-24)
                                            		tmp = (((1.0 - sqrt(x)) + (1.0 / (sqrt((y + 1.0)) + sqrt(y)))) + (sqrt((z + 1.0)) - sqrt(z))) + t_1;
                                            	else
                                            		tmp = ((sqrt((1.0 + x)) - sqrt(x)) + (0.5 * (1.0 / sqrt(z)))) + t_1;
                                            	end
                                            	tmp_2 = tmp;
                                            end
                                            
                                            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                            code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 1.7e-24], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision], N[(N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision]]]
                                            
                                            \begin{array}{l}
                                            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                            \\
                                            \begin{array}{l}
                                            t_1 := \sqrt{t + 1} - \sqrt{t}\\
                                            \mathbf{if}\;x \leq 1.7 \cdot 10^{-24}:\\
                                            \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + t\_1\\
                                            
                                            \mathbf{else}:\\
                                            \;\;\;\;\left(\left(\sqrt{1 + x} - \sqrt{x}\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + t\_1\\
                                            
                                            
                                            \end{array}
                                            \end{array}
                                            
                                            Derivation
                                            1. Split input into 2 regimes
                                            2. if x < 1.69999999999999996e-24

                                              1. Initial program 96.9%

                                                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              2. Step-by-step derivation
                                                1. lift--.f64N/A

                                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                2. lift-+.f64N/A

                                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                3. lift-sqrt.f64N/A

                                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                4. lift-sqrt.f64N/A

                                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                5. +-commutativeN/A

                                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                6. flip--N/A

                                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                7. lower-/.f64N/A

                                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              3. Applied rewrites97.1%

                                                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              4. Taylor expanded in y around 0

                                                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              5. Step-by-step derivation
                                                1. Applied rewrites98.1%

                                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                2. Taylor expanded in x around 0

                                                  \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                3. Step-by-step derivation
                                                  1. Applied rewrites98.1%

                                                    \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                                                  if 1.69999999999999996e-24 < x

                                                  1. Initial program 35.3%

                                                    \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  2. Step-by-step derivation
                                                    1. lift--.f64N/A

                                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\sqrt{y + 1} - \sqrt{y}\right)}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    2. lift-+.f64N/A

                                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    3. lift-sqrt.f64N/A

                                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\sqrt{y + 1}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    4. lift-sqrt.f64N/A

                                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \color{blue}{\sqrt{y}}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    5. +-commutativeN/A

                                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{\color{blue}{1 + y}} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    6. flip--N/A

                                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    7. lower-/.f64N/A

                                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  3. Applied rewrites35.6%

                                                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{y + 1} \cdot \sqrt{y + 1} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{y + 1} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  4. Taylor expanded in y around 0

                                                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  5. Step-by-step derivation
                                                    1. Applied rewrites40.3%

                                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\color{blue}{1}}{\sqrt{y + 1} + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    2. Taylor expanded in z around inf

                                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \color{blue}{\frac{1}{2} \cdot \sqrt{\frac{1}{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    3. Step-by-step derivation
                                                      1. lower-*.f64N/A

                                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \color{blue}{\sqrt{\frac{1}{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      2. sqrt-divN/A

                                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{\sqrt{1}}{\color{blue}{\sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      3. metadata-evalN/A

                                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{\color{blue}{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      4. lower-/.f64N/A

                                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      5. lift-sqrt.f6440.3

                                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    4. Applied rewrites40.3%

                                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \color{blue}{0.5 \cdot \frac{1}{\sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    5. Taylor expanded in y around inf

                                                      \[\leadsto \left(\color{blue}{\left(\sqrt{1 + x} - \sqrt{x}\right)} + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    6. Step-by-step derivation
                                                      1. lower--.f64N/A

                                                        \[\leadsto \left(\left(\sqrt{1 + x} - \color{blue}{\sqrt{x}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      2. lift-sqrt.f64N/A

                                                        \[\leadsto \left(\left(\sqrt{1 + x} - \sqrt{\color{blue}{x}}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      3. lift-+.f64N/A

                                                        \[\leadsto \left(\left(\sqrt{1 + x} - \sqrt{x}\right) + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      4. lift-sqrt.f6433.6

                                                        \[\leadsto \left(\left(\sqrt{1 + x} - \sqrt{x}\right) + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    7. Applied rewrites33.6%

                                                      \[\leadsto \left(\color{blue}{\left(\sqrt{1 + x} - \sqrt{x}\right)} + 0.5 \cdot \frac{1}{\sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  6. Recombined 2 regimes into one program.
                                                  7. Add Preprocessing

                                                  Alternative 18: 65.6% accurate, 1.8× speedup?

                                                  \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{1 + x}\\ \mathbf{if}\;y \leq 4.8 \cdot 10^{+15}:\\ \;\;\;\;\left(t\_1 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(t\_1 - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \end{array} \end{array} \]
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  (FPCore (x y z t)
                                                   :precision binary64
                                                   (let* ((t_1 (sqrt (+ 1.0 x))))
                                                     (if (<= y 4.8e+15)
                                                       (- (+ t_1 (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                                                       (+ (- t_1 (sqrt x)) (- (sqrt (+ t 1.0)) (sqrt t))))))
                                                  assert(x < y && y < z && z < t);
                                                  double code(double x, double y, double z, double t) {
                                                  	double t_1 = sqrt((1.0 + x));
                                                  	double tmp;
                                                  	if (y <= 4.8e+15) {
                                                  		tmp = (t_1 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                                                  	} else {
                                                  		tmp = (t_1 - sqrt(x)) + (sqrt((t + 1.0)) - sqrt(t));
                                                  	}
                                                  	return tmp;
                                                  }
                                                  
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  module fmin_fmax_functions
                                                      implicit none
                                                      private
                                                      public fmax
                                                      public fmin
                                                  
                                                      interface fmax
                                                          module procedure fmax88
                                                          module procedure fmax44
                                                          module procedure fmax84
                                                          module procedure fmax48
                                                      end interface
                                                      interface fmin
                                                          module procedure fmin88
                                                          module procedure fmin44
                                                          module procedure fmin84
                                                          module procedure fmin48
                                                      end interface
                                                  contains
                                                      real(8) function fmax88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmax44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmin44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                                      end function
                                                  end module
                                                  
                                                  real(8) function code(x, y, z, t)
                                                  use fmin_fmax_functions
                                                      real(8), intent (in) :: x
                                                      real(8), intent (in) :: y
                                                      real(8), intent (in) :: z
                                                      real(8), intent (in) :: t
                                                      real(8) :: t_1
                                                      real(8) :: tmp
                                                      t_1 = sqrt((1.0d0 + x))
                                                      if (y <= 4.8d+15) then
                                                          tmp = (t_1 + sqrt((1.0d0 + y))) - (sqrt(x) + sqrt(y))
                                                      else
                                                          tmp = (t_1 - sqrt(x)) + (sqrt((t + 1.0d0)) - sqrt(t))
                                                      end if
                                                      code = tmp
                                                  end function
                                                  
                                                  assert x < y && y < z && z < t;
                                                  public static double code(double x, double y, double z, double t) {
                                                  	double t_1 = Math.sqrt((1.0 + x));
                                                  	double tmp;
                                                  	if (y <= 4.8e+15) {
                                                  		tmp = (t_1 + Math.sqrt((1.0 + y))) - (Math.sqrt(x) + Math.sqrt(y));
                                                  	} else {
                                                  		tmp = (t_1 - Math.sqrt(x)) + (Math.sqrt((t + 1.0)) - Math.sqrt(t));
                                                  	}
                                                  	return tmp;
                                                  }
                                                  
                                                  [x, y, z, t] = sort([x, y, z, t])
                                                  def code(x, y, z, t):
                                                  	t_1 = math.sqrt((1.0 + x))
                                                  	tmp = 0
                                                  	if y <= 4.8e+15:
                                                  		tmp = (t_1 + math.sqrt((1.0 + y))) - (math.sqrt(x) + math.sqrt(y))
                                                  	else:
                                                  		tmp = (t_1 - math.sqrt(x)) + (math.sqrt((t + 1.0)) - math.sqrt(t))
                                                  	return tmp
                                                  
                                                  x, y, z, t = sort([x, y, z, t])
                                                  function code(x, y, z, t)
                                                  	t_1 = sqrt(Float64(1.0 + x))
                                                  	tmp = 0.0
                                                  	if (y <= 4.8e+15)
                                                  		tmp = Float64(Float64(t_1 + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
                                                  	else
                                                  		tmp = Float64(Float64(t_1 - sqrt(x)) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)));
                                                  	end
                                                  	return tmp
                                                  end
                                                  
                                                  x, y, z, t = num2cell(sort([x, y, z, t])){:}
                                                  function tmp_2 = code(x, y, z, t)
                                                  	t_1 = sqrt((1.0 + x));
                                                  	tmp = 0.0;
                                                  	if (y <= 4.8e+15)
                                                  		tmp = (t_1 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                                                  	else
                                                  		tmp = (t_1 - sqrt(x)) + (sqrt((t + 1.0)) - sqrt(t));
                                                  	end
                                                  	tmp_2 = tmp;
                                                  end
                                                  
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[y, 4.8e+15], N[(N[(t$95$1 + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(t$95$1 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
                                                  
                                                  \begin{array}{l}
                                                  [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                                  \\
                                                  \begin{array}{l}
                                                  t_1 := \sqrt{1 + x}\\
                                                  \mathbf{if}\;y \leq 4.8 \cdot 10^{+15}:\\
                                                  \;\;\;\;\left(t\_1 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
                                                  
                                                  \mathbf{else}:\\
                                                  \;\;\;\;\left(t\_1 - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\
                                                  
                                                  
                                                  \end{array}
                                                  \end{array}
                                                  
                                                  Derivation
                                                  1. Split input into 2 regimes
                                                  2. if y < 4.8e15

                                                    1. Initial program 96.8%

                                                      \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    2. Taylor expanded in t around inf

                                                      \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                                                    3. Step-by-step derivation
                                                      1. associate--r+N/A

                                                        \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                      2. lower--.f64N/A

                                                        \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                    4. Applied rewrites44.9%

                                                      \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                                                    5. Taylor expanded in z around inf

                                                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                                                    6. Step-by-step derivation
                                                      1. lower--.f64N/A

                                                        \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \color{blue}{\sqrt{y}}\right) \]
                                                      2. lower-+.f64N/A

                                                        \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{\color{blue}{y}}\right) \]
                                                      3. lift-sqrt.f64N/A

                                                        \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                      4. lift-+.f64N/A

                                                        \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                      5. lower-sqrt.f64N/A

                                                        \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                      6. lower-+.f64N/A

                                                        \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                      7. lower-+.f64N/A

                                                        \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                      8. lift-sqrt.f64N/A

                                                        \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                      9. lift-sqrt.f6460.7

                                                        \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                    7. Applied rewrites60.7%

                                                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]

                                                    if 4.8e15 < y

                                                    1. Initial program 78.7%

                                                      \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    2. Taylor expanded in z around inf

                                                      \[\leadsto \color{blue}{\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    3. Step-by-step derivation
                                                      1. associate--r+N/A

                                                        \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      2. lower--.f64N/A

                                                        \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \color{blue}{\sqrt{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      3. lower--.f64N/A

                                                        \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      4. lower-+.f64N/A

                                                        \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      5. +-commutativeN/A

                                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      6. lift-sqrt.f64N/A

                                                        \[\leadsto \left(\left(\left(\sqrt{x + 1} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      7. +-commutativeN/A

                                                        \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      8. lower-+.f64N/A

                                                        \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      9. +-commutativeN/A

                                                        \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      10. lift-sqrt.f64N/A

                                                        \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      11. lift-+.f64N/A

                                                        \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      12. lift-sqrt.f64N/A

                                                        \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      13. lift-sqrt.f6412.8

                                                        \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    4. Applied rewrites12.8%

                                                      \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) - \sqrt{x}\right) - \sqrt{y}\right)} + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    5. Taylor expanded in y around inf

                                                      \[\leadsto \left(\sqrt{1 + x} - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    6. Step-by-step derivation
                                                      1. lower--.f64N/A

                                                        \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      2. lift-sqrt.f64N/A

                                                        \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      3. lift-+.f64N/A

                                                        \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      4. lift-sqrt.f6478.7

                                                        \[\leadsto \left(\sqrt{1 + x} - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    7. Applied rewrites78.7%

                                                      \[\leadsto \left(\sqrt{1 + x} - \color{blue}{\sqrt{x}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  3. Recombined 2 regimes into one program.
                                                  4. Add Preprocessing

                                                  Alternative 19: 47.5% accurate, 2.0× speedup?

                                                  \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \end{array} \]
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  (FPCore (x y z t)
                                                   :precision binary64
                                                   (- (+ (sqrt (+ 1.0 x)) (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y))))
                                                  assert(x < y && y < z && z < t);
                                                  double code(double x, double y, double z, double t) {
                                                  	return (sqrt((1.0 + x)) + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                                                  }
                                                  
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  module fmin_fmax_functions
                                                      implicit none
                                                      private
                                                      public fmax
                                                      public fmin
                                                  
                                                      interface fmax
                                                          module procedure fmax88
                                                          module procedure fmax44
                                                          module procedure fmax84
                                                          module procedure fmax48
                                                      end interface
                                                      interface fmin
                                                          module procedure fmin88
                                                          module procedure fmin44
                                                          module procedure fmin84
                                                          module procedure fmin48
                                                      end interface
                                                  contains
                                                      real(8) function fmax88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmax44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmin44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                                      end function
                                                  end module
                                                  
                                                  real(8) function code(x, y, z, t)
                                                  use fmin_fmax_functions
                                                      real(8), intent (in) :: x
                                                      real(8), intent (in) :: y
                                                      real(8), intent (in) :: z
                                                      real(8), intent (in) :: t
                                                      code = (sqrt((1.0d0 + x)) + sqrt((1.0d0 + y))) - (sqrt(x) + sqrt(y))
                                                  end function
                                                  
                                                  assert x < y && y < z && z < t;
                                                  public static double code(double x, double y, double z, double t) {
                                                  	return (Math.sqrt((1.0 + x)) + Math.sqrt((1.0 + y))) - (Math.sqrt(x) + Math.sqrt(y));
                                                  }
                                                  
                                                  [x, y, z, t] = sort([x, y, z, t])
                                                  def code(x, y, z, t):
                                                  	return (math.sqrt((1.0 + x)) + math.sqrt((1.0 + y))) - (math.sqrt(x) + math.sqrt(y))
                                                  
                                                  x, y, z, t = sort([x, y, z, t])
                                                  function code(x, y, z, t)
                                                  	return Float64(Float64(sqrt(Float64(1.0 + x)) + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)))
                                                  end
                                                  
                                                  x, y, z, t = num2cell(sort([x, y, z, t])){:}
                                                  function tmp = code(x, y, z, t)
                                                  	tmp = (sqrt((1.0 + x)) + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                                                  end
                                                  
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  code[x_, y_, z_, t_] := N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                                                  
                                                  \begin{array}{l}
                                                  [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                                  \\
                                                  \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)
                                                  \end{array}
                                                  
                                                  Derivation
                                                  1. Initial program 91.8%

                                                    \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  2. Taylor expanded in t around inf

                                                    \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                                                  3. Step-by-step derivation
                                                    1. associate--r+N/A

                                                      \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                    2. lower--.f64N/A

                                                      \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                  4. Applied rewrites33.5%

                                                    \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                                                  5. Taylor expanded in z around inf

                                                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                                                  6. Step-by-step derivation
                                                    1. lower--.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \color{blue}{\sqrt{y}}\right) \]
                                                    2. lower-+.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{\color{blue}{y}}\right) \]
                                                    3. lift-sqrt.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                    4. lift-+.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                    5. lower-sqrt.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                    6. lower-+.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                    7. lower-+.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                    8. lift-sqrt.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                    9. lift-sqrt.f6447.5

                                                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                  7. Applied rewrites47.5%

                                                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                                                  8. Add Preprocessing

                                                  Alternative 20: 11.3% accurate, 2.7× speedup?

                                                  \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \end{array} \]
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  (FPCore (x y z t)
                                                   :precision binary64
                                                   (- (+ (sqrt (+ 1.0 y)) (sqrt (+ 1.0 z))) (sqrt y)))
                                                  assert(x < y && y < z && z < t);
                                                  double code(double x, double y, double z, double t) {
                                                  	return (sqrt((1.0 + y)) + sqrt((1.0 + z))) - sqrt(y);
                                                  }
                                                  
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  module fmin_fmax_functions
                                                      implicit none
                                                      private
                                                      public fmax
                                                      public fmin
                                                  
                                                      interface fmax
                                                          module procedure fmax88
                                                          module procedure fmax44
                                                          module procedure fmax84
                                                          module procedure fmax48
                                                      end interface
                                                      interface fmin
                                                          module procedure fmin88
                                                          module procedure fmin44
                                                          module procedure fmin84
                                                          module procedure fmin48
                                                      end interface
                                                  contains
                                                      real(8) function fmax88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmax44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmin44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                                      end function
                                                  end module
                                                  
                                                  real(8) function code(x, y, z, t)
                                                  use fmin_fmax_functions
                                                      real(8), intent (in) :: x
                                                      real(8), intent (in) :: y
                                                      real(8), intent (in) :: z
                                                      real(8), intent (in) :: t
                                                      code = (sqrt((1.0d0 + y)) + sqrt((1.0d0 + z))) - sqrt(y)
                                                  end function
                                                  
                                                  assert x < y && y < z && z < t;
                                                  public static double code(double x, double y, double z, double t) {
                                                  	return (Math.sqrt((1.0 + y)) + Math.sqrt((1.0 + z))) - Math.sqrt(y);
                                                  }
                                                  
                                                  [x, y, z, t] = sort([x, y, z, t])
                                                  def code(x, y, z, t):
                                                  	return (math.sqrt((1.0 + y)) + math.sqrt((1.0 + z))) - math.sqrt(y)
                                                  
                                                  x, y, z, t = sort([x, y, z, t])
                                                  function code(x, y, z, t)
                                                  	return Float64(Float64(sqrt(Float64(1.0 + y)) + sqrt(Float64(1.0 + z))) - sqrt(y))
                                                  end
                                                  
                                                  x, y, z, t = num2cell(sort([x, y, z, t])){:}
                                                  function tmp = code(x, y, z, t)
                                                  	tmp = (sqrt((1.0 + y)) + sqrt((1.0 + z))) - sqrt(y);
                                                  end
                                                  
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  code[x_, y_, z_, t_] := N[(N[(N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision] + N[Sqrt[N[(1.0 + z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]
                                                  
                                                  \begin{array}{l}
                                                  [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                                  \\
                                                  \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y}
                                                  \end{array}
                                                  
                                                  Derivation
                                                  1. Initial program 91.8%

                                                    \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  2. Taylor expanded in t around inf

                                                    \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                                                  3. Step-by-step derivation
                                                    1. associate--r+N/A

                                                      \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                    2. lower--.f64N/A

                                                      \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                  4. Applied rewrites33.5%

                                                    \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                                                  5. Taylor expanded in y around inf

                                                    \[\leadsto \sqrt{y} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                                                  6. Step-by-step derivation
                                                    1. lift-sqrt.f641.5

                                                      \[\leadsto \sqrt{y} - \left(\sqrt{z} + \sqrt{y}\right) \]
                                                  7. Applied rewrites1.5%

                                                    \[\leadsto \sqrt{y} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                                                  8. Taylor expanded in y around inf

                                                    \[\leadsto \sqrt{y} - \sqrt{y} \]
                                                  9. Step-by-step derivation
                                                    1. lift-sqrt.f643.1

                                                      \[\leadsto \sqrt{y} - \sqrt{y} \]
                                                  10. Applied rewrites3.1%

                                                    \[\leadsto \sqrt{y} - \sqrt{y} \]
                                                  11. Taylor expanded in x around inf

                                                    \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{\color{blue}{y}} \]
                                                  12. Step-by-step derivation
                                                    1. lower-+.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \]
                                                    2. lower-sqrt.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \]
                                                    3. lower-+.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \]
                                                    4. lift-sqrt.f64N/A

                                                      \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \]
                                                    5. lift-+.f6411.3

                                                      \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \]
                                                  13. Applied rewrites11.3%

                                                    \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{\color{blue}{y}} \]
                                                  14. Add Preprocessing

                                                  Alternative 21: 7.6% accurate, 4.8× speedup?

                                                  \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \sqrt{z} - \sqrt{y} \end{array} \]
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  (FPCore (x y z t) :precision binary64 (- (sqrt z) (sqrt y)))
                                                  assert(x < y && y < z && z < t);
                                                  double code(double x, double y, double z, double t) {
                                                  	return sqrt(z) - sqrt(y);
                                                  }
                                                  
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  module fmin_fmax_functions
                                                      implicit none
                                                      private
                                                      public fmax
                                                      public fmin
                                                  
                                                      interface fmax
                                                          module procedure fmax88
                                                          module procedure fmax44
                                                          module procedure fmax84
                                                          module procedure fmax48
                                                      end interface
                                                      interface fmin
                                                          module procedure fmin88
                                                          module procedure fmin44
                                                          module procedure fmin84
                                                          module procedure fmin48
                                                      end interface
                                                  contains
                                                      real(8) function fmax88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmax44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmin44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                                      end function
                                                  end module
                                                  
                                                  real(8) function code(x, y, z, t)
                                                  use fmin_fmax_functions
                                                      real(8), intent (in) :: x
                                                      real(8), intent (in) :: y
                                                      real(8), intent (in) :: z
                                                      real(8), intent (in) :: t
                                                      code = sqrt(z) - sqrt(y)
                                                  end function
                                                  
                                                  assert x < y && y < z && z < t;
                                                  public static double code(double x, double y, double z, double t) {
                                                  	return Math.sqrt(z) - Math.sqrt(y);
                                                  }
                                                  
                                                  [x, y, z, t] = sort([x, y, z, t])
                                                  def code(x, y, z, t):
                                                  	return math.sqrt(z) - math.sqrt(y)
                                                  
                                                  x, y, z, t = sort([x, y, z, t])
                                                  function code(x, y, z, t)
                                                  	return Float64(sqrt(z) - sqrt(y))
                                                  end
                                                  
                                                  x, y, z, t = num2cell(sort([x, y, z, t])){:}
                                                  function tmp = code(x, y, z, t)
                                                  	tmp = sqrt(z) - sqrt(y);
                                                  end
                                                  
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  code[x_, y_, z_, t_] := N[(N[Sqrt[z], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]
                                                  
                                                  \begin{array}{l}
                                                  [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                                  \\
                                                  \sqrt{z} - \sqrt{y}
                                                  \end{array}
                                                  
                                                  Derivation
                                                  1. Initial program 91.8%

                                                    \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  2. Taylor expanded in t around inf

                                                    \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                                                  3. Step-by-step derivation
                                                    1. associate--r+N/A

                                                      \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                    2. lower--.f64N/A

                                                      \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                  4. Applied rewrites33.5%

                                                    \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                                                  5. Taylor expanded in y around inf

                                                    \[\leadsto \sqrt{y} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                                                  6. Step-by-step derivation
                                                    1. lift-sqrt.f641.5

                                                      \[\leadsto \sqrt{y} - \left(\sqrt{z} + \sqrt{y}\right) \]
                                                  7. Applied rewrites1.5%

                                                    \[\leadsto \sqrt{y} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                                                  8. Taylor expanded in y around inf

                                                    \[\leadsto \sqrt{y} - \sqrt{y} \]
                                                  9. Step-by-step derivation
                                                    1. lift-sqrt.f643.1

                                                      \[\leadsto \sqrt{y} - \sqrt{y} \]
                                                  10. Applied rewrites3.1%

                                                    \[\leadsto \sqrt{y} - \sqrt{y} \]
                                                  11. Taylor expanded in z around inf

                                                    \[\leadsto \sqrt{z} - \sqrt{\color{blue}{y}} \]
                                                  12. Step-by-step derivation
                                                    1. lift-sqrt.f647.6

                                                      \[\leadsto \sqrt{z} - \sqrt{y} \]
                                                  13. Applied rewrites7.6%

                                                    \[\leadsto \sqrt{z} - \sqrt{\color{blue}{y}} \]
                                                  14. Add Preprocessing

                                                  Alternative 22: 3.1% accurate, 4.8× speedup?

                                                  \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \sqrt{y} - \sqrt{y} \end{array} \]
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  (FPCore (x y z t) :precision binary64 (- (sqrt y) (sqrt y)))
                                                  assert(x < y && y < z && z < t);
                                                  double code(double x, double y, double z, double t) {
                                                  	return sqrt(y) - sqrt(y);
                                                  }
                                                  
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  module fmin_fmax_functions
                                                      implicit none
                                                      private
                                                      public fmax
                                                      public fmin
                                                  
                                                      interface fmax
                                                          module procedure fmax88
                                                          module procedure fmax44
                                                          module procedure fmax84
                                                          module procedure fmax48
                                                      end interface
                                                      interface fmin
                                                          module procedure fmin88
                                                          module procedure fmin44
                                                          module procedure fmin84
                                                          module procedure fmin48
                                                      end interface
                                                  contains
                                                      real(8) function fmax88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmax44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmin44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                                      end function
                                                  end module
                                                  
                                                  real(8) function code(x, y, z, t)
                                                  use fmin_fmax_functions
                                                      real(8), intent (in) :: x
                                                      real(8), intent (in) :: y
                                                      real(8), intent (in) :: z
                                                      real(8), intent (in) :: t
                                                      code = sqrt(y) - sqrt(y)
                                                  end function
                                                  
                                                  assert x < y && y < z && z < t;
                                                  public static double code(double x, double y, double z, double t) {
                                                  	return Math.sqrt(y) - Math.sqrt(y);
                                                  }
                                                  
                                                  [x, y, z, t] = sort([x, y, z, t])
                                                  def code(x, y, z, t):
                                                  	return math.sqrt(y) - math.sqrt(y)
                                                  
                                                  x, y, z, t = sort([x, y, z, t])
                                                  function code(x, y, z, t)
                                                  	return Float64(sqrt(y) - sqrt(y))
                                                  end
                                                  
                                                  x, y, z, t = num2cell(sort([x, y, z, t])){:}
                                                  function tmp = code(x, y, z, t)
                                                  	tmp = sqrt(y) - sqrt(y);
                                                  end
                                                  
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  code[x_, y_, z_, t_] := N[(N[Sqrt[y], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]
                                                  
                                                  \begin{array}{l}
                                                  [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                                  \\
                                                  \sqrt{y} - \sqrt{y}
                                                  \end{array}
                                                  
                                                  Derivation
                                                  1. Initial program 91.8%

                                                    \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  2. Taylor expanded in t around inf

                                                    \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                                                  3. Step-by-step derivation
                                                    1. associate--r+N/A

                                                      \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                    2. lower--.f64N/A

                                                      \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                  4. Applied rewrites33.5%

                                                    \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)} \]
                                                  5. Taylor expanded in y around inf

                                                    \[\leadsto \sqrt{y} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                                                  6. Step-by-step derivation
                                                    1. lift-sqrt.f641.5

                                                      \[\leadsto \sqrt{y} - \left(\sqrt{z} + \sqrt{y}\right) \]
                                                  7. Applied rewrites1.5%

                                                    \[\leadsto \sqrt{y} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                                                  8. Taylor expanded in y around inf

                                                    \[\leadsto \sqrt{y} - \sqrt{y} \]
                                                  9. Step-by-step derivation
                                                    1. lift-sqrt.f643.1

                                                      \[\leadsto \sqrt{y} - \sqrt{y} \]
                                                  10. Applied rewrites3.1%

                                                    \[\leadsto \sqrt{y} - \sqrt{y} \]
                                                  11. Add Preprocessing

                                                  Developer Target 1: 99.4% accurate, 0.8× speedup?

                                                  \[\begin{array}{l} \\ \left(\left(\frac{1}{\sqrt{x + 1} + \sqrt{x}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \end{array} \]
                                                  (FPCore (x y z t)
                                                   :precision binary64
                                                   (+
                                                    (+
                                                     (+
                                                      (/ 1.0 (+ (sqrt (+ x 1.0)) (sqrt x)))
                                                      (/ 1.0 (+ (sqrt (+ y 1.0)) (sqrt y))))
                                                     (/ 1.0 (+ (sqrt (+ z 1.0)) (sqrt z))))
                                                    (- (sqrt (+ t 1.0)) (sqrt t))))
                                                  double code(double x, double y, double z, double t) {
                                                  	return (((1.0 / (sqrt((x + 1.0)) + sqrt(x))) + (1.0 / (sqrt((y + 1.0)) + sqrt(y)))) + (1.0 / (sqrt((z + 1.0)) + sqrt(z)))) + (sqrt((t + 1.0)) - sqrt(t));
                                                  }
                                                  
                                                  module fmin_fmax_functions
                                                      implicit none
                                                      private
                                                      public fmax
                                                      public fmin
                                                  
                                                      interface fmax
                                                          module procedure fmax88
                                                          module procedure fmax44
                                                          module procedure fmax84
                                                          module procedure fmax48
                                                      end interface
                                                      interface fmin
                                                          module procedure fmin88
                                                          module procedure fmin44
                                                          module procedure fmin84
                                                          module procedure fmin48
                                                      end interface
                                                  contains
                                                      real(8) function fmax88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmax44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmax48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin88(x, y) result (res)
                                                          real(8), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(4) function fmin44(x, y) result (res)
                                                          real(4), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin84(x, y) result(res)
                                                          real(8), intent (in) :: x
                                                          real(4), intent (in) :: y
                                                          res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                                      end function
                                                      real(8) function fmin48(x, y) result(res)
                                                          real(4), intent (in) :: x
                                                          real(8), intent (in) :: y
                                                          res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                                      end function
                                                  end module
                                                  
                                                  real(8) function code(x, y, z, t)
                                                  use fmin_fmax_functions
                                                      real(8), intent (in) :: x
                                                      real(8), intent (in) :: y
                                                      real(8), intent (in) :: z
                                                      real(8), intent (in) :: t
                                                      code = (((1.0d0 / (sqrt((x + 1.0d0)) + sqrt(x))) + (1.0d0 / (sqrt((y + 1.0d0)) + sqrt(y)))) + (1.0d0 / (sqrt((z + 1.0d0)) + sqrt(z)))) + (sqrt((t + 1.0d0)) - sqrt(t))
                                                  end function
                                                  
                                                  public static double code(double x, double y, double z, double t) {
                                                  	return (((1.0 / (Math.sqrt((x + 1.0)) + Math.sqrt(x))) + (1.0 / (Math.sqrt((y + 1.0)) + Math.sqrt(y)))) + (1.0 / (Math.sqrt((z + 1.0)) + Math.sqrt(z)))) + (Math.sqrt((t + 1.0)) - Math.sqrt(t));
                                                  }
                                                  
                                                  def code(x, y, z, t):
                                                  	return (((1.0 / (math.sqrt((x + 1.0)) + math.sqrt(x))) + (1.0 / (math.sqrt((y + 1.0)) + math.sqrt(y)))) + (1.0 / (math.sqrt((z + 1.0)) + math.sqrt(z)))) + (math.sqrt((t + 1.0)) - math.sqrt(t))
                                                  
                                                  function code(x, y, z, t)
                                                  	return Float64(Float64(Float64(Float64(1.0 / Float64(sqrt(Float64(x + 1.0)) + sqrt(x))) + Float64(1.0 / Float64(sqrt(Float64(y + 1.0)) + sqrt(y)))) + Float64(1.0 / Float64(sqrt(Float64(z + 1.0)) + sqrt(z)))) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)))
                                                  end
                                                  
                                                  function tmp = code(x, y, z, t)
                                                  	tmp = (((1.0 / (sqrt((x + 1.0)) + sqrt(x))) + (1.0 / (sqrt((y + 1.0)) + sqrt(y)))) + (1.0 / (sqrt((z + 1.0)) + sqrt(z)))) + (sqrt((t + 1.0)) - sqrt(t));
                                                  end
                                                  
                                                  code[x_, y_, z_, t_] := N[(N[(N[(N[(1.0 / N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                                                  
                                                  \begin{array}{l}
                                                  
                                                  \\
                                                  \left(\left(\frac{1}{\sqrt{x + 1} + \sqrt{x}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)
                                                  \end{array}
                                                  

                                                  Reproduce

                                                  ?
                                                  herbie shell --seed 2025106 
                                                  (FPCore (x y z t)
                                                    :name "Main:z from "
                                                    :precision binary64
                                                  
                                                    :alt
                                                    (! :herbie-platform default (+ (+ (+ (/ 1 (+ (sqrt (+ x 1)) (sqrt x))) (/ 1 (+ (sqrt (+ y 1)) (sqrt y)))) (/ 1 (+ (sqrt (+ z 1)) (sqrt z)))) (- (sqrt (+ t 1)) (sqrt t))))
                                                  
                                                    (+ (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y))) (- (sqrt (+ z 1.0)) (sqrt z))) (- (sqrt (+ t 1.0)) (sqrt t))))