Main:z from

Percentage Accurate: 91.7% → 99.0%
Time: 10.5s
Alternatives: 21
Speedup: 0.9×

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}

Sampling outcomes in binary64 precision:

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 21 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: 91.7% 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: 99.0% accurate, 0.5× speedup?

\[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ \mathbf{if}\;y \leq 56000000:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{t\_1 + \sqrt{z}}\right) + t\_2\\ \mathbf{else}:\\ \;\;\;\;\left(\mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, {\left(\sqrt{x} + \sqrt{1 + x}\right)}^{-1}\right) + \left(t\_1 - \sqrt{z}\right)\right) + t\_2\\ \end{array} \end{array} \]
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))) (t_2 (- (sqrt (+ t 1.0)) (sqrt t))))
   (if (<= y 56000000.0)
     (+
      (+
       (+ (- 1.0 (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
       (/ 1.0 (+ t_1 (sqrt z))))
      t_2)
     (+
      (+
       (fma 0.5 (/ 1.0 (sqrt y)) (pow (+ (sqrt x) (sqrt (+ 1.0 x))) -1.0))
       (- t_1 (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));
	double t_2 = sqrt((t + 1.0)) - sqrt(t);
	double tmp;
	if (y <= 56000000.0) {
		tmp = (((1.0 - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (1.0 / (t_1 + sqrt(z)))) + t_2;
	} else {
		tmp = (fma(0.5, (1.0 / sqrt(y)), pow((sqrt(x) + sqrt((1.0 + x))), -1.0)) + (t_1 - sqrt(z))) + t_2;
	}
	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))
	tmp = 0.0
	if (y <= 56000000.0)
		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + Float64(sqrt(Float64(y + 1.0)) - sqrt(y))) + Float64(1.0 / Float64(t_1 + sqrt(z)))) + t_2);
	else
		tmp = Float64(Float64(fma(0.5, Float64(1.0 / sqrt(y)), (Float64(sqrt(x) + sqrt(Float64(1.0 + x))) ^ -1.0)) + Float64(t_1 - 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[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]}, If[LessEqual[y, 56000000.0], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(t$95$1 + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision], N[(N[(N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision] + N[Power[N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], -1.0], $MachinePrecision]), $MachinePrecision] + N[(t$95$1 - 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}\\
t_2 := \sqrt{t + 1} - \sqrt{t}\\
\mathbf{if}\;y \leq 56000000:\\
\;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{t\_1 + \sqrt{z}}\right) + t\_2\\

\mathbf{else}:\\
\;\;\;\;\left(\mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, {\left(\sqrt{x} + \sqrt{1 + x}\right)}^{-1}\right) + \left(t\_1 - \sqrt{z}\right)\right) + t\_2\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < 5.6e7

    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. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

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

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

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

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

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

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

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

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

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

        \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      3. Step-by-step derivation
        1. Applied rewrites49.5%

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

        if 5.6e7 < y

        1. Initial program 83.9%

          \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        2. Add Preprocessing
        3. 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

            \[\leadsto \left(\left(\color{blue}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{1 + x} + \sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        4. Applied rewrites83.9%

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \frac{1}{\sqrt{y}}, {\left(\sqrt{x} + \sqrt{1 + x}\right)}^{-1}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          11. lift-+.f6493.3

            \[\leadsto \left(\mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, {\left(\sqrt{x} + \sqrt{1 + x}\right)}^{-1}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        7. Applied rewrites93.3%

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

      Alternative 2: 98.1% accurate, 0.3× speedup?

      \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1} - \sqrt{y}\\ t_2 := \sqrt{z + 1}\\ t_3 := t\_2 - \sqrt{z}\\ t_4 := \frac{1}{t\_2 + \sqrt{z}}\\ t_5 := \sqrt{x + 1} - \sqrt{x}\\ t_6 := \sqrt{t + 1} - \sqrt{t}\\ t_7 := \left(\left(t\_5 + t\_1\right) + t\_3\right) + t\_6\\ \mathbf{if}\;t\_7 \leq 5 \cdot 10^{-6}:\\ \;\;\;\;\left(\left(\frac{0.5 \cdot \sqrt{x}}{x} + t\_1\right) + t\_4\right) + t\_6\\ \mathbf{elif}\;t\_7 \leq 1.00005:\\ \;\;\;\;\left(\left(t\_5 + \frac{0.5 \cdot \sqrt{y}}{y}\right) + t\_3\right) + t\_6\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_1\right) + t\_4\right) + t\_6\\ \end{array} \end{array} \]
      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)) (sqrt y)))
              (t_2 (sqrt (+ z 1.0)))
              (t_3 (- t_2 (sqrt z)))
              (t_4 (/ 1.0 (+ t_2 (sqrt z))))
              (t_5 (- (sqrt (+ x 1.0)) (sqrt x)))
              (t_6 (- (sqrt (+ t 1.0)) (sqrt t)))
              (t_7 (+ (+ (+ t_5 t_1) t_3) t_6)))
         (if (<= t_7 5e-6)
           (+ (+ (+ (/ (* 0.5 (sqrt x)) x) t_1) t_4) t_6)
           (if (<= t_7 1.00005)
             (+ (+ (+ t_5 (/ (* 0.5 (sqrt y)) y)) t_3) t_6)
             (+ (+ (+ (- 1.0 (sqrt x)) t_1) t_4) 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)) - sqrt(y);
      	double t_2 = sqrt((z + 1.0));
      	double t_3 = t_2 - sqrt(z);
      	double t_4 = 1.0 / (t_2 + sqrt(z));
      	double t_5 = sqrt((x + 1.0)) - sqrt(x);
      	double t_6 = sqrt((t + 1.0)) - sqrt(t);
      	double t_7 = ((t_5 + t_1) + t_3) + t_6;
      	double tmp;
      	if (t_7 <= 5e-6) {
      		tmp = ((((0.5 * sqrt(x)) / x) + t_1) + t_4) + t_6;
      	} else if (t_7 <= 1.00005) {
      		tmp = ((t_5 + ((0.5 * sqrt(y)) / y)) + t_3) + t_6;
      	} else {
      		tmp = (((1.0 - sqrt(x)) + t_1) + t_4) + t_6;
      	}
      	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) :: t_6
          real(8) :: t_7
          real(8) :: tmp
          t_1 = sqrt((y + 1.0d0)) - sqrt(y)
          t_2 = sqrt((z + 1.0d0))
          t_3 = t_2 - sqrt(z)
          t_4 = 1.0d0 / (t_2 + sqrt(z))
          t_5 = sqrt((x + 1.0d0)) - sqrt(x)
          t_6 = sqrt((t + 1.0d0)) - sqrt(t)
          t_7 = ((t_5 + t_1) + t_3) + t_6
          if (t_7 <= 5d-6) then
              tmp = ((((0.5d0 * sqrt(x)) / x) + t_1) + t_4) + t_6
          else if (t_7 <= 1.00005d0) then
              tmp = ((t_5 + ((0.5d0 * sqrt(y)) / y)) + t_3) + t_6
          else
              tmp = (((1.0d0 - sqrt(x)) + t_1) + t_4) + t_6
          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)) - Math.sqrt(y);
      	double t_2 = Math.sqrt((z + 1.0));
      	double t_3 = t_2 - Math.sqrt(z);
      	double t_4 = 1.0 / (t_2 + Math.sqrt(z));
      	double t_5 = Math.sqrt((x + 1.0)) - Math.sqrt(x);
      	double t_6 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
      	double t_7 = ((t_5 + t_1) + t_3) + t_6;
      	double tmp;
      	if (t_7 <= 5e-6) {
      		tmp = ((((0.5 * Math.sqrt(x)) / x) + t_1) + t_4) + t_6;
      	} else if (t_7 <= 1.00005) {
      		tmp = ((t_5 + ((0.5 * Math.sqrt(y)) / y)) + t_3) + t_6;
      	} else {
      		tmp = (((1.0 - Math.sqrt(x)) + t_1) + t_4) + t_6;
      	}
      	return tmp;
      }
      
      [x, y, z, t] = sort([x, y, z, t])
      def code(x, y, z, t):
      	t_1 = math.sqrt((y + 1.0)) - math.sqrt(y)
      	t_2 = math.sqrt((z + 1.0))
      	t_3 = t_2 - math.sqrt(z)
      	t_4 = 1.0 / (t_2 + math.sqrt(z))
      	t_5 = math.sqrt((x + 1.0)) - math.sqrt(x)
      	t_6 = math.sqrt((t + 1.0)) - math.sqrt(t)
      	t_7 = ((t_5 + t_1) + t_3) + t_6
      	tmp = 0
      	if t_7 <= 5e-6:
      		tmp = ((((0.5 * math.sqrt(x)) / x) + t_1) + t_4) + t_6
      	elif t_7 <= 1.00005:
      		tmp = ((t_5 + ((0.5 * math.sqrt(y)) / y)) + t_3) + t_6
      	else:
      		tmp = (((1.0 - math.sqrt(x)) + t_1) + t_4) + t_6
      	return tmp
      
      x, y, z, t = sort([x, y, z, t])
      function code(x, y, z, t)
      	t_1 = Float64(sqrt(Float64(y + 1.0)) - sqrt(y))
      	t_2 = sqrt(Float64(z + 1.0))
      	t_3 = Float64(t_2 - sqrt(z))
      	t_4 = Float64(1.0 / Float64(t_2 + sqrt(z)))
      	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_1) + t_3) + t_6)
      	tmp = 0.0
      	if (t_7 <= 5e-6)
      		tmp = Float64(Float64(Float64(Float64(Float64(0.5 * sqrt(x)) / x) + t_1) + t_4) + t_6);
      	elseif (t_7 <= 1.00005)
      		tmp = Float64(Float64(Float64(t_5 + Float64(Float64(0.5 * sqrt(y)) / y)) + t_3) + t_6);
      	else
      		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + t_1) + t_4) + t_6);
      	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)) - sqrt(y);
      	t_2 = sqrt((z + 1.0));
      	t_3 = t_2 - sqrt(z);
      	t_4 = 1.0 / (t_2 + sqrt(z));
      	t_5 = sqrt((x + 1.0)) - sqrt(x);
      	t_6 = sqrt((t + 1.0)) - sqrt(t);
      	t_7 = ((t_5 + t_1) + t_3) + t_6;
      	tmp = 0.0;
      	if (t_7 <= 5e-6)
      		tmp = ((((0.5 * sqrt(x)) / x) + t_1) + t_4) + t_6;
      	elseif (t_7 <= 1.00005)
      		tmp = ((t_5 + ((0.5 * sqrt(y)) / y)) + t_3) + t_6;
      	else
      		tmp = (((1.0 - sqrt(x)) + t_1) + t_4) + t_6;
      	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[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[(t$95$2 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(1.0 / N[(t$95$2 + N[Sqrt[z], $MachinePrecision]), $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$1), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$6), $MachinePrecision]}, If[LessEqual[t$95$7, 5e-6], N[(N[(N[(N[(N[(0.5 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$4), $MachinePrecision] + t$95$6), $MachinePrecision], If[LessEqual[t$95$7, 1.00005], N[(N[(N[(t$95$5 + N[(N[(0.5 * N[Sqrt[y], $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$6), $MachinePrecision], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$4), $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} - \sqrt{y}\\
      t_2 := \sqrt{z + 1}\\
      t_3 := t\_2 - \sqrt{z}\\
      t_4 := \frac{1}{t\_2 + \sqrt{z}}\\
      t_5 := \sqrt{x + 1} - \sqrt{x}\\
      t_6 := \sqrt{t + 1} - \sqrt{t}\\
      t_7 := \left(\left(t\_5 + t\_1\right) + t\_3\right) + t\_6\\
      \mathbf{if}\;t\_7 \leq 5 \cdot 10^{-6}:\\
      \;\;\;\;\left(\left(\frac{0.5 \cdot \sqrt{x}}{x} + t\_1\right) + t\_4\right) + t\_6\\
      
      \mathbf{elif}\;t\_7 \leq 1.00005:\\
      \;\;\;\;\left(\left(t\_5 + \frac{0.5 \cdot \sqrt{y}}{y}\right) + t\_3\right) + t\_6\\
      
      \mathbf{else}:\\
      \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_1\right) + t\_4\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))) < 5.00000000000000041e-6

        1. Initial program 6.8%

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

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

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

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

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

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

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \color{blue}{\frac{\sqrt{z + 1} \cdot \sqrt{z + 1} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{z + 1} + \sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        4. Applied rewrites6.8%

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

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{\color{blue}{1}}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        6. Step-by-step derivation
          1. Applied rewrites27.7%

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

            \[\leadsto \left(\left(\color{blue}{\frac{\frac{-1}{8} \cdot \sqrt{\frac{1}{x}} + \frac{1}{2} \cdot \sqrt{x}}{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          3. Step-by-step derivation
            1. lower-/.f64N/A

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

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

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

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

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

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

              \[\leadsto \left(\left(\frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{x}}, \frac{1}{2} \cdot \sqrt{x}\right)}{x} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            8. lift-sqrt.f6465.9

              \[\leadsto \left(\left(\frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{x}}, 0.5 \cdot \sqrt{x}\right)}{x} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          4. Applied rewrites65.9%

            \[\leadsto \left(\left(\color{blue}{\frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{x}}, 0.5 \cdot \sqrt{x}\right)}{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          5. Taylor expanded in x around inf

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

              \[\leadsto \left(\left(\frac{\frac{1}{2} \cdot \sqrt{x}}{x} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. lift-*.f6466.0

              \[\leadsto \left(\left(\frac{0.5 \cdot \sqrt{x}}{x} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          7. Applied rewrites66.0%

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

          if 5.00000000000000041e-6 < (+.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))) < 1.00005000000000011

          1. Initial program 94.9%

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

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\frac{-1}{8} \cdot \sqrt{\frac{1}{y}} + \frac{1}{2} \cdot \sqrt{y}}{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          4. Step-by-step derivation
            1. lower-/.f64N/A

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\frac{-1}{8} \cdot \sqrt{\frac{1}{y}} + \frac{1}{2} \cdot \sqrt{y}}{\color{blue}{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. *-commutativeN/A

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

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

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

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

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

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

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

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{-1}{8}, \frac{1}{2} \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            10. lift-sqrt.f6471.8

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, -0.125, 0.5 \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          5. Applied rewrites71.8%

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, -0.125, 0.5 \cdot \sqrt{y}\right)}{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          6. Taylor expanded in y around inf

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

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\frac{1}{2} \cdot \sqrt{y}}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. lift-*.f6473.4

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{0.5 \cdot \sqrt{y}}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          8. Applied rewrites73.4%

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

          if 1.00005000000000011 < (+.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. Add Preprocessing
          3. Step-by-step derivation
            1. lift--.f64N/A

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

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

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

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

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

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \color{blue}{\frac{\sqrt{z + 1} \cdot \sqrt{z + 1} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{z + 1} + \sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          4. Applied rewrites97.4%

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

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{\color{blue}{1}}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          6. Step-by-step derivation
            1. Applied rewrites97.9%

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

              \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            3. Step-by-step derivation
              1. Applied rewrites64.4%

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

            Alternative 3: 98.1% accurate, 0.3× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1} - \sqrt{y}\\ t_2 := \sqrt{z + 1}\\ t_3 := t\_2 - \sqrt{z}\\ t_4 := \frac{1}{t\_2 + \sqrt{z}}\\ t_5 := \sqrt{x + 1} - \sqrt{x}\\ t_6 := \sqrt{t + 1} - \sqrt{t}\\ t_7 := \left(\left(t\_5 + t\_1\right) + t\_3\right) + t\_6\\ \mathbf{if}\;t\_7 \leq 5 \cdot 10^{-6}:\\ \;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + t\_1\right) + t\_4\right) + t\_6\\ \mathbf{elif}\;t\_7 \leq 1.00005:\\ \;\;\;\;\left(\left(t\_5 + \frac{0.5 \cdot \sqrt{y}}{y}\right) + t\_3\right) + t\_6\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_1\right) + t\_4\right) + t\_6\\ \end{array} \end{array} \]
            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)) (sqrt y)))
                    (t_2 (sqrt (+ z 1.0)))
                    (t_3 (- t_2 (sqrt z)))
                    (t_4 (/ 1.0 (+ t_2 (sqrt z))))
                    (t_5 (- (sqrt (+ x 1.0)) (sqrt x)))
                    (t_6 (- (sqrt (+ t 1.0)) (sqrt t)))
                    (t_7 (+ (+ (+ t_5 t_1) t_3) t_6)))
               (if (<= t_7 5e-6)
                 (+ (+ (+ (* 0.5 (/ 1.0 (sqrt x))) t_1) t_4) t_6)
                 (if (<= t_7 1.00005)
                   (+ (+ (+ t_5 (/ (* 0.5 (sqrt y)) y)) t_3) t_6)
                   (+ (+ (+ (- 1.0 (sqrt x)) t_1) t_4) 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)) - sqrt(y);
            	double t_2 = sqrt((z + 1.0));
            	double t_3 = t_2 - sqrt(z);
            	double t_4 = 1.0 / (t_2 + sqrt(z));
            	double t_5 = sqrt((x + 1.0)) - sqrt(x);
            	double t_6 = sqrt((t + 1.0)) - sqrt(t);
            	double t_7 = ((t_5 + t_1) + t_3) + t_6;
            	double tmp;
            	if (t_7 <= 5e-6) {
            		tmp = (((0.5 * (1.0 / sqrt(x))) + t_1) + t_4) + t_6;
            	} else if (t_7 <= 1.00005) {
            		tmp = ((t_5 + ((0.5 * sqrt(y)) / y)) + t_3) + t_6;
            	} else {
            		tmp = (((1.0 - sqrt(x)) + t_1) + t_4) + t_6;
            	}
            	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) :: t_6
                real(8) :: t_7
                real(8) :: tmp
                t_1 = sqrt((y + 1.0d0)) - sqrt(y)
                t_2 = sqrt((z + 1.0d0))
                t_3 = t_2 - sqrt(z)
                t_4 = 1.0d0 / (t_2 + sqrt(z))
                t_5 = sqrt((x + 1.0d0)) - sqrt(x)
                t_6 = sqrt((t + 1.0d0)) - sqrt(t)
                t_7 = ((t_5 + t_1) + t_3) + t_6
                if (t_7 <= 5d-6) then
                    tmp = (((0.5d0 * (1.0d0 / sqrt(x))) + t_1) + t_4) + t_6
                else if (t_7 <= 1.00005d0) then
                    tmp = ((t_5 + ((0.5d0 * sqrt(y)) / y)) + t_3) + t_6
                else
                    tmp = (((1.0d0 - sqrt(x)) + t_1) + t_4) + t_6
                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)) - Math.sqrt(y);
            	double t_2 = Math.sqrt((z + 1.0));
            	double t_3 = t_2 - Math.sqrt(z);
            	double t_4 = 1.0 / (t_2 + Math.sqrt(z));
            	double t_5 = Math.sqrt((x + 1.0)) - Math.sqrt(x);
            	double t_6 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
            	double t_7 = ((t_5 + t_1) + t_3) + t_6;
            	double tmp;
            	if (t_7 <= 5e-6) {
            		tmp = (((0.5 * (1.0 / Math.sqrt(x))) + t_1) + t_4) + t_6;
            	} else if (t_7 <= 1.00005) {
            		tmp = ((t_5 + ((0.5 * Math.sqrt(y)) / y)) + t_3) + t_6;
            	} else {
            		tmp = (((1.0 - Math.sqrt(x)) + t_1) + t_4) + t_6;
            	}
            	return tmp;
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	t_1 = math.sqrt((y + 1.0)) - math.sqrt(y)
            	t_2 = math.sqrt((z + 1.0))
            	t_3 = t_2 - math.sqrt(z)
            	t_4 = 1.0 / (t_2 + math.sqrt(z))
            	t_5 = math.sqrt((x + 1.0)) - math.sqrt(x)
            	t_6 = math.sqrt((t + 1.0)) - math.sqrt(t)
            	t_7 = ((t_5 + t_1) + t_3) + t_6
            	tmp = 0
            	if t_7 <= 5e-6:
            		tmp = (((0.5 * (1.0 / math.sqrt(x))) + t_1) + t_4) + t_6
            	elif t_7 <= 1.00005:
            		tmp = ((t_5 + ((0.5 * math.sqrt(y)) / y)) + t_3) + t_6
            	else:
            		tmp = (((1.0 - math.sqrt(x)) + t_1) + t_4) + t_6
            	return tmp
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	t_1 = Float64(sqrt(Float64(y + 1.0)) - sqrt(y))
            	t_2 = sqrt(Float64(z + 1.0))
            	t_3 = Float64(t_2 - sqrt(z))
            	t_4 = Float64(1.0 / Float64(t_2 + sqrt(z)))
            	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_1) + t_3) + t_6)
            	tmp = 0.0
            	if (t_7 <= 5e-6)
            		tmp = Float64(Float64(Float64(Float64(0.5 * Float64(1.0 / sqrt(x))) + t_1) + t_4) + t_6);
            	elseif (t_7 <= 1.00005)
            		tmp = Float64(Float64(Float64(t_5 + Float64(Float64(0.5 * sqrt(y)) / y)) + t_3) + t_6);
            	else
            		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + t_1) + t_4) + t_6);
            	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)) - sqrt(y);
            	t_2 = sqrt((z + 1.0));
            	t_3 = t_2 - sqrt(z);
            	t_4 = 1.0 / (t_2 + sqrt(z));
            	t_5 = sqrt((x + 1.0)) - sqrt(x);
            	t_6 = sqrt((t + 1.0)) - sqrt(t);
            	t_7 = ((t_5 + t_1) + t_3) + t_6;
            	tmp = 0.0;
            	if (t_7 <= 5e-6)
            		tmp = (((0.5 * (1.0 / sqrt(x))) + t_1) + t_4) + t_6;
            	elseif (t_7 <= 1.00005)
            		tmp = ((t_5 + ((0.5 * sqrt(y)) / y)) + t_3) + t_6;
            	else
            		tmp = (((1.0 - sqrt(x)) + t_1) + t_4) + t_6;
            	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[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[(t$95$2 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(1.0 / N[(t$95$2 + N[Sqrt[z], $MachinePrecision]), $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$1), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$6), $MachinePrecision]}, If[LessEqual[t$95$7, 5e-6], N[(N[(N[(N[(0.5 * N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$4), $MachinePrecision] + t$95$6), $MachinePrecision], If[LessEqual[t$95$7, 1.00005], N[(N[(N[(t$95$5 + N[(N[(0.5 * N[Sqrt[y], $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$6), $MachinePrecision], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$4), $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} - \sqrt{y}\\
            t_2 := \sqrt{z + 1}\\
            t_3 := t\_2 - \sqrt{z}\\
            t_4 := \frac{1}{t\_2 + \sqrt{z}}\\
            t_5 := \sqrt{x + 1} - \sqrt{x}\\
            t_6 := \sqrt{t + 1} - \sqrt{t}\\
            t_7 := \left(\left(t\_5 + t\_1\right) + t\_3\right) + t\_6\\
            \mathbf{if}\;t\_7 \leq 5 \cdot 10^{-6}:\\
            \;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + t\_1\right) + t\_4\right) + t\_6\\
            
            \mathbf{elif}\;t\_7 \leq 1.00005:\\
            \;\;\;\;\left(\left(t\_5 + \frac{0.5 \cdot \sqrt{y}}{y}\right) + t\_3\right) + t\_6\\
            
            \mathbf{else}:\\
            \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_1\right) + t\_4\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))) < 5.00000000000000041e-6

              1. Initial program 6.8%

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

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

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

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

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

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

                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \color{blue}{\frac{\sqrt{z + 1} \cdot \sqrt{z + 1} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{z + 1} + \sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              4. Applied rewrites6.8%

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

                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{\color{blue}{1}}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              6. Step-by-step derivation
                1. Applied rewrites27.7%

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

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

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

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

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

                    \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  5. lift-sqrt.f6465.7

                    \[\leadsto \left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                4. Applied rewrites65.7%

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

                if 5.00000000000000041e-6 < (+.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))) < 1.00005000000000011

                1. Initial program 94.9%

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

                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\frac{-1}{8} \cdot \sqrt{\frac{1}{y}} + \frac{1}{2} \cdot \sqrt{y}}{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                4. Step-by-step derivation
                  1. lower-/.f64N/A

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\frac{-1}{8} \cdot \sqrt{\frac{1}{y}} + \frac{1}{2} \cdot \sqrt{y}}{\color{blue}{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. *-commutativeN/A

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

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

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

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

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

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

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

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{-1}{8}, \frac{1}{2} \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  10. lift-sqrt.f6471.8

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, -0.125, 0.5 \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                5. Applied rewrites71.8%

                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, -0.125, 0.5 \cdot \sqrt{y}\right)}{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                6. Taylor expanded in y around inf

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

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\frac{1}{2} \cdot \sqrt{y}}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  2. lift-*.f6473.4

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{0.5 \cdot \sqrt{y}}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                8. Applied rewrites73.4%

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

                if 1.00005000000000011 < (+.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. Add Preprocessing
                3. Step-by-step derivation
                  1. lift--.f64N/A

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

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

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

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

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

                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \color{blue}{\frac{\sqrt{z + 1} \cdot \sqrt{z + 1} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{z + 1} + \sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                4. Applied rewrites97.4%

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

                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{\color{blue}{1}}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                6. Step-by-step derivation
                  1. Applied rewrites97.9%

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

                    \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. Step-by-step derivation
                    1. Applied rewrites64.4%

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

                  Alternative 4: 92.7% accurate, 0.4× speedup?

                  \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{z + 1}\\ t_3 := \sqrt{t + 1} - \sqrt{t}\\ t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_2 - \sqrt{z}\right)\right) + t\_3\\ \mathbf{if}\;t\_4 \leq 1.00005:\\ \;\;\;\;\left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + t\_3\\ \mathbf{elif}\;t\_4 \leq 2.0005:\\ \;\;\;\;\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + 0.5 \cdot \frac{1}{\sqrt{z}}\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(t\_1 + 1\right) + \mathsf{fma}\left(0.5, x, t\_2\right)\right) - \sqrt{z}\right) + t\_3\\ \end{array} \end{array} \]
                  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)))
                          (t_3 (- (sqrt (+ t 1.0)) (sqrt t)))
                          (t_4
                           (+
                            (+
                             (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- t_1 (sqrt y)))
                             (- t_2 (sqrt z)))
                            t_3)))
                     (if (<= t_4 1.00005)
                       (+ (- (+ 1.0 (fma 0.5 x (* 0.5 (/ 1.0 (sqrt y))))) (sqrt x)) t_3)
                       (if (<= t_4 2.0005)
                         (-
                          (+ (sqrt (+ 1.0 x)) (+ (sqrt (+ 1.0 y)) (* 0.5 (/ 1.0 (sqrt z)))))
                          (+ (sqrt x) (sqrt y)))
                         (+ (- (+ (+ t_1 1.0) (fma 0.5 x t_2)) (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((z + 1.0));
                  	double t_3 = sqrt((t + 1.0)) - sqrt(t);
                  	double t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_1 - sqrt(y))) + (t_2 - sqrt(z))) + t_3;
                  	double tmp;
                  	if (t_4 <= 1.00005) {
                  		tmp = ((1.0 + fma(0.5, x, (0.5 * (1.0 / sqrt(y))))) - sqrt(x)) + t_3;
                  	} else if (t_4 <= 2.0005) {
                  		tmp = (sqrt((1.0 + x)) + (sqrt((1.0 + y)) + (0.5 * (1.0 / sqrt(z))))) - (sqrt(x) + sqrt(y));
                  	} else {
                  		tmp = (((t_1 + 1.0) + fma(0.5, x, t_2)) - 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(z + 1.0))
                  	t_3 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                  	t_4 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(t_1 - sqrt(y))) + Float64(t_2 - sqrt(z))) + t_3)
                  	tmp = 0.0
                  	if (t_4 <= 1.00005)
                  		tmp = Float64(Float64(Float64(1.0 + fma(0.5, x, Float64(0.5 * Float64(1.0 / sqrt(y))))) - sqrt(x)) + t_3);
                  	elseif (t_4 <= 2.0005)
                  		tmp = Float64(Float64(sqrt(Float64(1.0 + x)) + Float64(sqrt(Float64(1.0 + y)) + Float64(0.5 * Float64(1.0 / sqrt(z))))) - Float64(sqrt(x) + sqrt(y)));
                  	else
                  		tmp = Float64(Float64(Float64(Float64(t_1 + 1.0) + fma(0.5, x, t_2)) - 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[(z + 1.0), $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[(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$2 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision]}, If[LessEqual[t$95$4, 1.00005], N[(N[(N[(1.0 + N[(0.5 * x + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision], If[LessEqual[t$95$4, 2.0005], N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[(N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(t$95$1 + 1.0), $MachinePrecision] + N[(0.5 * x + t$95$2), $MachinePrecision]), $MachinePrecision] - N[Sqrt[z], $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{z + 1}\\
                  t_3 := \sqrt{t + 1} - \sqrt{t}\\
                  t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_2 - \sqrt{z}\right)\right) + t\_3\\
                  \mathbf{if}\;t\_4 \leq 1.00005:\\
                  \;\;\;\;\left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + t\_3\\
                  
                  \mathbf{elif}\;t\_4 \leq 2.0005:\\
                  \;\;\;\;\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + 0.5 \cdot \frac{1}{\sqrt{z}}\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;\left(\left(\left(t\_1 + 1\right) + \mathsf{fma}\left(0.5, x, t\_2\right)\right) - \sqrt{z}\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))) < 1.00005000000000011

                    1. Initial program 73.7%

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

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

                        \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot x\right)\right)\right) - \color{blue}{\left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    5. Applied rewrites12.1%

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

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

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

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

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

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

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

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

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

                        \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \frac{1}{2} \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      9. lift-sqrt.f6410.7

                        \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + 0.5 \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    8. Applied rewrites10.7%

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

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

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

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

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

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

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

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

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

                        \[\leadsto \left(\left(1 + \mathsf{fma}\left(\frac{1}{2}, x, \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      9. lift-sqrt.f6425.5

                        \[\leadsto \left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    11. Applied rewrites25.5%

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

                    if 1.00005000000000011 < (+.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))) < 2.00050000000000017

                    1. Initial program 96.2%

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

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

                        \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                    5. Applied rewrites4.8%

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

                      \[\leadsto \sqrt{z} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                    7. Step-by-step derivation
                      1. lift-sqrt.f642.1

                        \[\leadsto \sqrt{z} - \left(\sqrt{z} + \sqrt{y}\right) \]
                    8. Applied rewrites2.1%

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

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

                        \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \frac{1}{2} \cdot \sqrt{\frac{1}{z}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{y}}\right) \]
                    11. Applied rewrites19.5%

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

                    if 2.00050000000000017 < (+.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 98.7%

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

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

                        \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot x\right)\right)\right) - \color{blue}{\left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    5. Applied rewrites44.4%

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

                      \[\leadsto \left(\left(\left(\sqrt{y + 1} + 1\right) + \mathsf{fma}\left(\frac{1}{2}, x, \sqrt{z + 1}\right)\right) - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    7. Step-by-step derivation
                      1. lift-sqrt.f6440.1

                        \[\leadsto \left(\left(\left(\sqrt{y + 1} + 1\right) + \mathsf{fma}\left(0.5, x, \sqrt{z + 1}\right)\right) - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    8. Applied rewrites40.1%

                      \[\leadsto \left(\left(\left(\sqrt{y + 1} + 1\right) + \mathsf{fma}\left(0.5, x, \sqrt{z + 1}\right)\right) - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. Recombined 3 regimes into one program.
                  4. Final simplification27.9%

                    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \leq 1.00005:\\ \;\;\;\;\left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{elif}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \leq 2.0005:\\ \;\;\;\;\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + 0.5 \cdot \frac{1}{\sqrt{z}}\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\sqrt{y + 1} + 1\right) + \mathsf{fma}\left(0.5, x, \sqrt{z + 1}\right)\right) - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \end{array} \]
                  5. Add Preprocessing

                  Alternative 5: 91.7% accurate, 0.4× speedup?

                  \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{z + 1}\\ t_3 := \sqrt{t + 1} - \sqrt{t}\\ t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_2 - \sqrt{z}\right)\right) + t\_3\\ \mathbf{if}\;t\_4 \leq 1.00005:\\ \;\;\;\;\left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + t\_3\\ \mathbf{elif}\;t\_4 \leq 2:\\ \;\;\;\;\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(t\_1 + 1\right) + \mathsf{fma}\left(0.5, x, t\_2\right)\right) - \sqrt{z}\right) + t\_3\\ \end{array} \end{array} \]
                  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)))
                          (t_3 (- (sqrt (+ t 1.0)) (sqrt t)))
                          (t_4
                           (+
                            (+
                             (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- t_1 (sqrt y)))
                             (- t_2 (sqrt z)))
                            t_3)))
                     (if (<= t_4 1.00005)
                       (+ (- (+ 1.0 (fma 0.5 x (* 0.5 (/ 1.0 (sqrt y))))) (sqrt x)) t_3)
                       (if (<= t_4 2.0)
                         (- (+ (sqrt (+ 1.0 x)) (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                         (+ (- (+ (+ t_1 1.0) (fma 0.5 x t_2)) (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((z + 1.0));
                  	double t_3 = sqrt((t + 1.0)) - sqrt(t);
                  	double t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_1 - sqrt(y))) + (t_2 - sqrt(z))) + t_3;
                  	double tmp;
                  	if (t_4 <= 1.00005) {
                  		tmp = ((1.0 + fma(0.5, x, (0.5 * (1.0 / sqrt(y))))) - sqrt(x)) + t_3;
                  	} else if (t_4 <= 2.0) {
                  		tmp = (sqrt((1.0 + x)) + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                  	} else {
                  		tmp = (((t_1 + 1.0) + fma(0.5, x, t_2)) - 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(z + 1.0))
                  	t_3 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                  	t_4 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(t_1 - sqrt(y))) + Float64(t_2 - sqrt(z))) + t_3)
                  	tmp = 0.0
                  	if (t_4 <= 1.00005)
                  		tmp = Float64(Float64(Float64(1.0 + fma(0.5, x, Float64(0.5 * Float64(1.0 / sqrt(y))))) - sqrt(x)) + t_3);
                  	elseif (t_4 <= 2.0)
                  		tmp = Float64(Float64(sqrt(Float64(1.0 + x)) + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
                  	else
                  		tmp = Float64(Float64(Float64(Float64(t_1 + 1.0) + fma(0.5, x, t_2)) - 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[(z + 1.0), $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[(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$2 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision]}, If[LessEqual[t$95$4, 1.00005], N[(N[(N[(1.0 + N[(0.5 * x + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision], If[LessEqual[t$95$4, 2.0], 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], N[(N[(N[(N[(t$95$1 + 1.0), $MachinePrecision] + N[(0.5 * x + t$95$2), $MachinePrecision]), $MachinePrecision] - N[Sqrt[z], $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{z + 1}\\
                  t_3 := \sqrt{t + 1} - \sqrt{t}\\
                  t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_2 - \sqrt{z}\right)\right) + t\_3\\
                  \mathbf{if}\;t\_4 \leq 1.00005:\\
                  \;\;\;\;\left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + t\_3\\
                  
                  \mathbf{elif}\;t\_4 \leq 2:\\
                  \;\;\;\;\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;\left(\left(\left(t\_1 + 1\right) + \mathsf{fma}\left(0.5, x, t\_2\right)\right) - \sqrt{z}\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))) < 1.00005000000000011

                    1. Initial program 73.7%

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

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

                        \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot x\right)\right)\right) - \color{blue}{\left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    5. Applied rewrites12.1%

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

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

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

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

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

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

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

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

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

                        \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \frac{1}{2} \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      9. lift-sqrt.f6410.7

                        \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + 0.5 \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    8. Applied rewrites10.7%

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

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

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

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

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

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

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

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

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

                        \[\leadsto \left(\left(1 + \mathsf{fma}\left(\frac{1}{2}, x, \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      9. lift-sqrt.f6425.5

                        \[\leadsto \left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    11. Applied rewrites25.5%

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

                    if 1.00005000000000011 < (+.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 98.0%

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

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

                        \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                    5. Applied rewrites4.4%

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

                      \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                    7. 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.f6418.9

                        \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                    8. Applied rewrites18.9%

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

                    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 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. Add Preprocessing
                    3. Taylor expanded in x around 0

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

                        \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot x\right)\right)\right) - \color{blue}{\left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    5. Applied rewrites42.1%

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

                      \[\leadsto \left(\left(\left(\sqrt{y + 1} + 1\right) + \mathsf{fma}\left(\frac{1}{2}, x, \sqrt{z + 1}\right)\right) - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    7. Step-by-step derivation
                      1. lift-sqrt.f6438.0

                        \[\leadsto \left(\left(\left(\sqrt{y + 1} + 1\right) + \mathsf{fma}\left(0.5, x, \sqrt{z + 1}\right)\right) - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    8. Applied rewrites38.0%

                      \[\leadsto \left(\left(\left(\sqrt{y + 1} + 1\right) + \mathsf{fma}\left(0.5, x, \sqrt{z + 1}\right)\right) - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                  3. Recombined 3 regimes into one program.
                  4. Final simplification27.6%

                    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \leq 1.00005:\\ \;\;\;\;\left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{elif}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \leq 2:\\ \;\;\;\;\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\sqrt{y + 1} + 1\right) + \mathsf{fma}\left(0.5, x, \sqrt{z + 1}\right)\right) - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \end{array} \]
                  5. Add Preprocessing

                  Alternative 6: 98.1% accurate, 0.4× speedup?

                  \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1}\\ t_2 := \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\\ t_3 := \sqrt{t + 1} - \sqrt{t}\\ t_4 := \frac{1}{t\_1 + \sqrt{z}}\\ \mathbf{if}\;\left(t\_2 + \left(t\_1 - \sqrt{z}\right)\right) + t\_3 \leq 0.0005:\\ \;\;\;\;\left(\left(\frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{x}}, 0.5 \cdot \sqrt{x}\right)}{x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) + t\_4\right) + t\_3\\ \mathbf{else}:\\ \;\;\;\;\left(t\_2 + t\_4\right) + t\_3\\ \end{array} \end{array} \]
                  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 (+ z 1.0)))
                          (t_2 (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y))))
                          (t_3 (- (sqrt (+ t 1.0)) (sqrt t)))
                          (t_4 (/ 1.0 (+ t_1 (sqrt z)))))
                     (if (<= (+ (+ t_2 (- t_1 (sqrt z))) t_3) 0.0005)
                       (+
                        (+
                         (+
                          (/ (fma -0.125 (/ 1.0 (sqrt x)) (* 0.5 (sqrt x))) x)
                          (* 0.5 (/ 1.0 (sqrt y))))
                         t_4)
                        t_3)
                       (+ (+ t_2 t_4) t_3))))
                  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((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y));
                  	double t_3 = sqrt((t + 1.0)) - sqrt(t);
                  	double t_4 = 1.0 / (t_1 + sqrt(z));
                  	double tmp;
                  	if (((t_2 + (t_1 - sqrt(z))) + t_3) <= 0.0005) {
                  		tmp = (((fma(-0.125, (1.0 / sqrt(x)), (0.5 * sqrt(x))) / x) + (0.5 * (1.0 / sqrt(y)))) + t_4) + t_3;
                  	} else {
                  		tmp = (t_2 + t_4) + t_3;
                  	}
                  	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(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(sqrt(Float64(y + 1.0)) - sqrt(y)))
                  	t_3 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                  	t_4 = Float64(1.0 / Float64(t_1 + sqrt(z)))
                  	tmp = 0.0
                  	if (Float64(Float64(t_2 + Float64(t_1 - sqrt(z))) + t_3) <= 0.0005)
                  		tmp = Float64(Float64(Float64(Float64(fma(-0.125, Float64(1.0 / sqrt(x)), Float64(0.5 * sqrt(x))) / x) + Float64(0.5 * Float64(1.0 / sqrt(y)))) + t_4) + t_3);
                  	else
                  		tmp = Float64(Float64(t_2 + t_4) + 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[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = 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]}, Block[{t$95$3 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(1.0 / N[(t$95$1 + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(t$95$2 + N[(t$95$1 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision], 0.0005], N[(N[(N[(N[(N[(-0.125 * N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(0.5 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$4), $MachinePrecision] + t$95$3), $MachinePrecision], N[(N[(t$95$2 + t$95$4), $MachinePrecision] + t$95$3), $MachinePrecision]]]]]]
                  
                  \begin{array}{l}
                  [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                  \\
                  \begin{array}{l}
                  t_1 := \sqrt{z + 1}\\
                  t_2 := \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\\
                  t_3 := \sqrt{t + 1} - \sqrt{t}\\
                  t_4 := \frac{1}{t\_1 + \sqrt{z}}\\
                  \mathbf{if}\;\left(t\_2 + \left(t\_1 - \sqrt{z}\right)\right) + t\_3 \leq 0.0005:\\
                  \;\;\;\;\left(\left(\frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{x}}, 0.5 \cdot \sqrt{x}\right)}{x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) + t\_4\right) + t\_3\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;\left(t\_2 + t\_4\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))) < 5.0000000000000001e-4

                    1. Initial program 10.2%

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

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

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

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

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

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

                        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \color{blue}{\frac{\sqrt{z + 1} \cdot \sqrt{z + 1} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{z + 1} + \sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    4. Applied rewrites10.2%

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

                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{\color{blue}{1}}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                    6. Step-by-step derivation
                      1. Applied rewrites30.2%

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

                        \[\leadsto \left(\left(\color{blue}{\frac{\frac{-1}{8} \cdot \sqrt{\frac{1}{x}} + \frac{1}{2} \cdot \sqrt{x}}{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      3. Step-by-step derivation
                        1. lower-/.f64N/A

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

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

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

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

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

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

                          \[\leadsto \left(\left(\frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{x}}, \frac{1}{2} \cdot \sqrt{x}\right)}{x} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        8. lift-sqrt.f6466.4

                          \[\leadsto \left(\left(\frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{x}}, 0.5 \cdot \sqrt{x}\right)}{x} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      4. Applied rewrites66.4%

                        \[\leadsto \left(\left(\color{blue}{\frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{x}}, 0.5 \cdot \sqrt{x}\right)}{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      5. Taylor expanded in y around inf

                        \[\leadsto \left(\left(\frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{x}}, \frac{1}{2} \cdot \sqrt{x}\right)}{x} + \color{blue}{\frac{1}{2} \cdot \sqrt{\frac{1}{y}}}\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      6. Step-by-step derivation
                        1. lower-*.f64N/A

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

                          \[\leadsto \left(\left(\frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{x}}, \frac{1}{2} \cdot \sqrt{x}\right)}{x} + \frac{1}{2} \cdot \frac{\sqrt{1}}{\color{blue}{\sqrt{y}}}\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        3. metadata-evalN/A

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

                          \[\leadsto \left(\left(\frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{x}}, \frac{1}{2} \cdot \sqrt{x}\right)}{x} + \frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{y}}}\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        5. lift-sqrt.f6483.6

                          \[\leadsto \left(\left(\frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{x}}, 0.5 \cdot \sqrt{x}\right)}{x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                      7. Applied rewrites83.6%

                        \[\leadsto \left(\left(\frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{x}}, 0.5 \cdot \sqrt{x}\right)}{x} + \color{blue}{0.5 \cdot \frac{1}{\sqrt{y}}}\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]

                      if 5.0000000000000001e-4 < (+.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 96.8%

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

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

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

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

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

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

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

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

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

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

                      Alternative 7: 86.5% accurate, 0.5× speedup?

                      \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1}\\ t_2 := \left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(t\_1 - \sqrt{z}\right)\\ t_3 := \sqrt{1 + x}\\ \mathbf{if}\;t\_2 \leq 1.00005:\\ \;\;\;\;\left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{elif}\;t\_2 \leq 2:\\ \;\;\;\;\left(t\_3 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(t\_3 + 1\right) + t\_1\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)\\ \end{array} \end{array} \]
                      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 (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
                                (- t_1 (sqrt z))))
                              (t_3 (sqrt (+ 1.0 x))))
                         (if (<= t_2 1.00005)
                           (+
                            (- (+ 1.0 (fma 0.5 x (* 0.5 (/ 1.0 (sqrt y))))) (sqrt x))
                            (- (sqrt (+ t 1.0)) (sqrt t)))
                           (if (<= t_2 2.0)
                             (- (+ t_3 (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                             (- (- (+ (+ t_3 1.0) 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((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (t_1 - sqrt(z));
                      	double t_3 = sqrt((1.0 + x));
                      	double tmp;
                      	if (t_2 <= 1.00005) {
                      		tmp = ((1.0 + fma(0.5, x, (0.5 * (1.0 / sqrt(y))))) - sqrt(x)) + (sqrt((t + 1.0)) - sqrt(t));
                      	} else if (t_2 <= 2.0) {
                      		tmp = (t_3 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                      	} else {
                      		tmp = (((t_3 + 1.0) + t_1) - sqrt(x)) - (sqrt(z) + 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(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(sqrt(Float64(y + 1.0)) - sqrt(y))) + Float64(t_1 - sqrt(z)))
                      	t_3 = sqrt(Float64(1.0 + x))
                      	tmp = 0.0
                      	if (t_2 <= 1.00005)
                      		tmp = Float64(Float64(Float64(1.0 + fma(0.5, x, Float64(0.5 * Float64(1.0 / sqrt(y))))) - sqrt(x)) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)));
                      	elseif (t_2 <= 2.0)
                      		tmp = Float64(Float64(t_3 + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
                      	else
                      		tmp = Float64(Float64(Float64(Float64(t_3 + 1.0) + t_1) - sqrt(x)) - Float64(sqrt(z) + sqrt(y)));
                      	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[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = 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[(t$95$1 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$2, 1.00005], N[(N[(N[(1.0 + N[(0.5 * x + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$2, 2.0], N[(N[(t$95$3 + 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$3 + 1.0), $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 := \left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(t\_1 - \sqrt{z}\right)\\
                      t_3 := \sqrt{1 + x}\\
                      \mathbf{if}\;t\_2 \leq 1.00005:\\
                      \;\;\;\;\left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\
                      
                      \mathbf{elif}\;t\_2 \leq 2:\\
                      \;\;\;\;\left(t\_3 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
                      
                      \mathbf{else}:\\
                      \;\;\;\;\left(\left(\left(t\_3 + 1\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 (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))) < 1.00005000000000011

                        1. Initial program 83.0%

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

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

                            \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot x\right)\right)\right) - \color{blue}{\left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        5. Applied rewrites12.3%

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

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

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

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

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

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

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

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

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

                            \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \frac{1}{2} \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          9. lift-sqrt.f6412.3

                            \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + 0.5 \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        8. Applied rewrites12.3%

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

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

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

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

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

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

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

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

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

                            \[\leadsto \left(\left(1 + \mathsf{fma}\left(\frac{1}{2}, x, \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          9. lift-sqrt.f6432.8

                            \[\leadsto \left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                        11. Applied rewrites32.8%

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

                        if 1.00005000000000011 < (+.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))) < 2

                        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. Add Preprocessing
                        3. Taylor expanded in t around inf

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

                            \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                        5. Applied rewrites4.8%

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

                          \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                        7. 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.f6420.8

                            \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                        8. Applied rewrites20.8%

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

                        if 2 < (+.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)))

                        1. Initial program 98.4%

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

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

                            \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                        5. Applied rewrites52.1%

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

                          \[\leadsto \left(\left(\left(\sqrt{1 + x} + 1\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
                        7. Step-by-step derivation
                          1. Applied rewrites50.1%

                            \[\leadsto \left(\left(\left(\sqrt{1 + x} + 1\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
                        8. Recombined 3 regimes into one program.
                        9. Final simplification30.3%

                          \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right) \leq 1.00005:\\ \;\;\;\;\left(\left(1 + \mathsf{fma}\left(0.5, x, 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{elif}\;\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right) \leq 2:\\ \;\;\;\;\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\sqrt{1 + x} + 1\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)\\ \end{array} \]
                        10. Add Preprocessing

                        Alternative 8: 85.5% accurate, 0.5× speedup?

                        \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1}\\ t_2 := \left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(t\_1 - \sqrt{z}\right)\\ t_3 := \sqrt{1 + x}\\ \mathbf{if}\;t\_2 \leq 1:\\ \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{elif}\;t\_2 \leq 2:\\ \;\;\;\;\left(t\_3 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(t\_3 + 1\right) + t\_1\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)\\ \end{array} \end{array} \]
                        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 (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
                                  (- t_1 (sqrt z))))
                                (t_3 (sqrt (+ 1.0 x))))
                           (if (<= t_2 1.0)
                             (+ (- (+ 1.0 (* 0.5 x)) (sqrt x)) (- (sqrt (+ t 1.0)) (sqrt t)))
                             (if (<= t_2 2.0)
                               (- (+ t_3 (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                               (- (- (+ (+ t_3 1.0) 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((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (t_1 - sqrt(z));
                        	double t_3 = sqrt((1.0 + x));
                        	double tmp;
                        	if (t_2 <= 1.0) {
                        		tmp = ((1.0 + (0.5 * x)) - sqrt(x)) + (sqrt((t + 1.0)) - sqrt(t));
                        	} else if (t_2 <= 2.0) {
                        		tmp = (t_3 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                        	} else {
                        		tmp = (((t_3 + 1.0) + 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) :: tmp
                            t_1 = sqrt((z + 1.0d0))
                            t_2 = ((sqrt((x + 1.0d0)) - sqrt(x)) + (sqrt((y + 1.0d0)) - sqrt(y))) + (t_1 - sqrt(z))
                            t_3 = sqrt((1.0d0 + x))
                            if (t_2 <= 1.0d0) then
                                tmp = ((1.0d0 + (0.5d0 * x)) - sqrt(x)) + (sqrt((t + 1.0d0)) - sqrt(t))
                            else if (t_2 <= 2.0d0) then
                                tmp = (t_3 + sqrt((1.0d0 + y))) - (sqrt(x) + sqrt(y))
                            else
                                tmp = (((t_3 + 1.0d0) + 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((x + 1.0)) - Math.sqrt(x)) + (Math.sqrt((y + 1.0)) - Math.sqrt(y))) + (t_1 - Math.sqrt(z));
                        	double t_3 = Math.sqrt((1.0 + x));
                        	double tmp;
                        	if (t_2 <= 1.0) {
                        		tmp = ((1.0 + (0.5 * x)) - Math.sqrt(x)) + (Math.sqrt((t + 1.0)) - Math.sqrt(t));
                        	} else if (t_2 <= 2.0) {
                        		tmp = (t_3 + Math.sqrt((1.0 + y))) - (Math.sqrt(x) + Math.sqrt(y));
                        	} else {
                        		tmp = (((t_3 + 1.0) + 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((x + 1.0)) - math.sqrt(x)) + (math.sqrt((y + 1.0)) - math.sqrt(y))) + (t_1 - math.sqrt(z))
                        	t_3 = math.sqrt((1.0 + x))
                        	tmp = 0
                        	if t_2 <= 1.0:
                        		tmp = ((1.0 + (0.5 * x)) - math.sqrt(x)) + (math.sqrt((t + 1.0)) - math.sqrt(t))
                        	elif t_2 <= 2.0:
                        		tmp = (t_3 + math.sqrt((1.0 + y))) - (math.sqrt(x) + math.sqrt(y))
                        	else:
                        		tmp = (((t_3 + 1.0) + 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(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(sqrt(Float64(y + 1.0)) - sqrt(y))) + Float64(t_1 - sqrt(z)))
                        	t_3 = sqrt(Float64(1.0 + x))
                        	tmp = 0.0
                        	if (t_2 <= 1.0)
                        		tmp = Float64(Float64(Float64(1.0 + Float64(0.5 * x)) - sqrt(x)) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)));
                        	elseif (t_2 <= 2.0)
                        		tmp = Float64(Float64(t_3 + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
                        	else
                        		tmp = Float64(Float64(Float64(Float64(t_3 + 1.0) + 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((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (t_1 - sqrt(z));
                        	t_3 = sqrt((1.0 + x));
                        	tmp = 0.0;
                        	if (t_2 <= 1.0)
                        		tmp = ((1.0 + (0.5 * x)) - sqrt(x)) + (sqrt((t + 1.0)) - sqrt(t));
                        	elseif (t_2 <= 2.0)
                        		tmp = (t_3 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                        	else
                        		tmp = (((t_3 + 1.0) + 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[(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[(t$95$1 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$2, 1.0], N[(N[(N[(1.0 + N[(0.5 * x), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$2, 2.0], N[(N[(t$95$3 + 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$3 + 1.0), $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 := \left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(t\_1 - \sqrt{z}\right)\\
                        t_3 := \sqrt{1 + x}\\
                        \mathbf{if}\;t\_2 \leq 1:\\
                        \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\
                        
                        \mathbf{elif}\;t\_2 \leq 2:\\
                        \;\;\;\;\left(t\_3 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
                        
                        \mathbf{else}:\\
                        \;\;\;\;\left(\left(\left(t\_3 + 1\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 (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))) < 1

                          1. Initial program 83.2%

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

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

                              \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot x\right)\right)\right) - \color{blue}{\left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          5. Applied rewrites12.6%

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

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

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

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

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

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

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

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

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

                              \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \frac{1}{2} \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            9. lift-sqrt.f6411.9

                              \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + 0.5 \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          8. Applied rewrites11.9%

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

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

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

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

                              \[\leadsto \left(\left(1 + \frac{1}{2} \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            4. lift-sqrt.f6433.3

                              \[\leadsto \left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                          11. Applied rewrites33.3%

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

                          if 1 < (+.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))) < 2

                          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. Add Preprocessing
                          3. Taylor expanded in t around inf

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

                              \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                          5. Applied rewrites4.8%

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

                            \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                          7. 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.f6421.4

                              \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                          8. Applied rewrites21.4%

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

                          if 2 < (+.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)))

                          1. Initial program 98.4%

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

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

                              \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                          5. Applied rewrites52.1%

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

                            \[\leadsto \left(\left(\left(\sqrt{1 + x} + 1\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
                          7. Step-by-step derivation
                            1. Applied rewrites50.1%

                              \[\leadsto \left(\left(\left(\sqrt{1 + x} + 1\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right) \]
                          8. Recombined 3 regimes into one program.
                          9. Final simplification30.5%

                            \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right) \leq 1:\\ \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{elif}\;\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right) \leq 2:\\ \;\;\;\;\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\sqrt{1 + x} + 1\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \left(\sqrt{z} + \sqrt{y}\right)\\ \end{array} \]
                          10. Add Preprocessing

                          Alternative 9: 85.3% accurate, 0.5× speedup?

                          \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1}\\ t_2 := \left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(t\_1 - \sqrt{z}\right)\\ t_3 := \sqrt{1 + x}\\ \mathbf{if}\;t\_2 \leq 1:\\ \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{elif}\;t\_2 \leq 2:\\ \;\;\;\;\left(t\_3 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(t\_3 + 1\right) + t\_1\right) - \sqrt{x}\right) - \sqrt{z}\\ \end{array} \end{array} \]
                          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 (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
                                    (- t_1 (sqrt z))))
                                  (t_3 (sqrt (+ 1.0 x))))
                             (if (<= t_2 1.0)
                               (+ (- (+ 1.0 (* 0.5 x)) (sqrt x)) (- (sqrt (+ t 1.0)) (sqrt t)))
                               (if (<= t_2 2.0)
                                 (- (+ t_3 (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                                 (- (- (+ (+ t_3 1.0) 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((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (t_1 - sqrt(z));
                          	double t_3 = sqrt((1.0 + x));
                          	double tmp;
                          	if (t_2 <= 1.0) {
                          		tmp = ((1.0 + (0.5 * x)) - sqrt(x)) + (sqrt((t + 1.0)) - sqrt(t));
                          	} else if (t_2 <= 2.0) {
                          		tmp = (t_3 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                          	} else {
                          		tmp = (((t_3 + 1.0) + 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) :: tmp
                              t_1 = sqrt((z + 1.0d0))
                              t_2 = ((sqrt((x + 1.0d0)) - sqrt(x)) + (sqrt((y + 1.0d0)) - sqrt(y))) + (t_1 - sqrt(z))
                              t_3 = sqrt((1.0d0 + x))
                              if (t_2 <= 1.0d0) then
                                  tmp = ((1.0d0 + (0.5d0 * x)) - sqrt(x)) + (sqrt((t + 1.0d0)) - sqrt(t))
                              else if (t_2 <= 2.0d0) then
                                  tmp = (t_3 + sqrt((1.0d0 + y))) - (sqrt(x) + sqrt(y))
                              else
                                  tmp = (((t_3 + 1.0d0) + 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((x + 1.0)) - Math.sqrt(x)) + (Math.sqrt((y + 1.0)) - Math.sqrt(y))) + (t_1 - Math.sqrt(z));
                          	double t_3 = Math.sqrt((1.0 + x));
                          	double tmp;
                          	if (t_2 <= 1.0) {
                          		tmp = ((1.0 + (0.5 * x)) - Math.sqrt(x)) + (Math.sqrt((t + 1.0)) - Math.sqrt(t));
                          	} else if (t_2 <= 2.0) {
                          		tmp = (t_3 + Math.sqrt((1.0 + y))) - (Math.sqrt(x) + Math.sqrt(y));
                          	} else {
                          		tmp = (((t_3 + 1.0) + 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((x + 1.0)) - math.sqrt(x)) + (math.sqrt((y + 1.0)) - math.sqrt(y))) + (t_1 - math.sqrt(z))
                          	t_3 = math.sqrt((1.0 + x))
                          	tmp = 0
                          	if t_2 <= 1.0:
                          		tmp = ((1.0 + (0.5 * x)) - math.sqrt(x)) + (math.sqrt((t + 1.0)) - math.sqrt(t))
                          	elif t_2 <= 2.0:
                          		tmp = (t_3 + math.sqrt((1.0 + y))) - (math.sqrt(x) + math.sqrt(y))
                          	else:
                          		tmp = (((t_3 + 1.0) + 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(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(sqrt(Float64(y + 1.0)) - sqrt(y))) + Float64(t_1 - sqrt(z)))
                          	t_3 = sqrt(Float64(1.0 + x))
                          	tmp = 0.0
                          	if (t_2 <= 1.0)
                          		tmp = Float64(Float64(Float64(1.0 + Float64(0.5 * x)) - sqrt(x)) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)));
                          	elseif (t_2 <= 2.0)
                          		tmp = Float64(Float64(t_3 + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
                          	else
                          		tmp = Float64(Float64(Float64(Float64(t_3 + 1.0) + 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((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (t_1 - sqrt(z));
                          	t_3 = sqrt((1.0 + x));
                          	tmp = 0.0;
                          	if (t_2 <= 1.0)
                          		tmp = ((1.0 + (0.5 * x)) - sqrt(x)) + (sqrt((t + 1.0)) - sqrt(t));
                          	elseif (t_2 <= 2.0)
                          		tmp = (t_3 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                          	else
                          		tmp = (((t_3 + 1.0) + 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[(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[(t$95$1 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$2, 1.0], N[(N[(N[(1.0 + N[(0.5 * x), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$2, 2.0], N[(N[(t$95$3 + 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$3 + 1.0), $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 := \left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(t\_1 - \sqrt{z}\right)\\
                          t_3 := \sqrt{1 + x}\\
                          \mathbf{if}\;t\_2 \leq 1:\\
                          \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\
                          
                          \mathbf{elif}\;t\_2 \leq 2:\\
                          \;\;\;\;\left(t\_3 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
                          
                          \mathbf{else}:\\
                          \;\;\;\;\left(\left(\left(t\_3 + 1\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 (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))) < 1

                            1. Initial program 83.2%

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

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

                                \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot x\right)\right)\right) - \color{blue}{\left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            5. Applied rewrites12.6%

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

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

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

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

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

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

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

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

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

                                \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \frac{1}{2} \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              9. lift-sqrt.f6411.9

                                \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + 0.5 \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            8. Applied rewrites11.9%

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

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

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

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

                                \[\leadsto \left(\left(1 + \frac{1}{2} \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              4. lift-sqrt.f6433.3

                                \[\leadsto \left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                            11. Applied rewrites33.3%

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

                            if 1 < (+.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))) < 2

                            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. Add Preprocessing
                            3. Taylor expanded in t around inf

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

                                \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                            5. Applied rewrites4.8%

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

                              \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                            7. 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.f6421.4

                                \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                            8. Applied rewrites21.4%

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

                            if 2 < (+.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)))

                            1. Initial program 98.4%

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

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

                                \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                            5. Applied rewrites52.1%

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

                              \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z} \]
                            7. Step-by-step derivation
                              1. lift-sqrt.f6449.8

                                \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z} \]
                            8. Applied rewrites49.8%

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

                              \[\leadsto \left(\left(\left(\sqrt{1 + x} + 1\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z} \]
                            10. Step-by-step derivation
                              1. Applied rewrites49.8%

                                \[\leadsto \left(\left(\left(\sqrt{1 + x} + 1\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z} \]
                            11. Recombined 3 regimes into one program.
                            12. Final simplification30.5%

                              \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right) \leq 1:\\ \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{elif}\;\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right) \leq 2:\\ \;\;\;\;\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\sqrt{1 + x} + 1\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z}\\ \end{array} \]
                            13. Add Preprocessing

                            Alternative 10: 81.3% accurate, 0.5× speedup?

                            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\\ t_2 := \sqrt{1 + y}\\ \mathbf{if}\;t\_1 \leq 1:\\ \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{elif}\;t\_1 \leq 2.5:\\ \;\;\;\;\left(\sqrt{1 + x} + t\_2\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(1 + \left(t\_2 + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \sqrt{y}\\ \end{array} \end{array} \]
                            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 (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
                                      (- (sqrt (+ z 1.0)) (sqrt z))))
                                    (t_2 (sqrt (+ 1.0 y))))
                               (if (<= t_1 1.0)
                                 (+ (- (+ 1.0 (* 0.5 x)) (sqrt x)) (- (sqrt (+ t 1.0)) (sqrt t)))
                                 (if (<= t_1 2.5)
                                   (- (+ (sqrt (+ 1.0 x)) t_2) (+ (sqrt x) (sqrt y)))
                                   (- (- (+ 1.0 (+ t_2 (sqrt (+ 1.0 z)))) (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((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z));
                            	double t_2 = sqrt((1.0 + y));
                            	double tmp;
                            	if (t_1 <= 1.0) {
                            		tmp = ((1.0 + (0.5 * x)) - sqrt(x)) + (sqrt((t + 1.0)) - sqrt(t));
                            	} else if (t_1 <= 2.5) {
                            		tmp = (sqrt((1.0 + x)) + t_2) - (sqrt(x) + sqrt(y));
                            	} else {
                            		tmp = ((1.0 + (t_2 + sqrt((1.0 + z)))) - 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) :: tmp
                                t_1 = ((sqrt((x + 1.0d0)) - sqrt(x)) + (sqrt((y + 1.0d0)) - sqrt(y))) + (sqrt((z + 1.0d0)) - sqrt(z))
                                t_2 = sqrt((1.0d0 + y))
                                if (t_1 <= 1.0d0) then
                                    tmp = ((1.0d0 + (0.5d0 * x)) - sqrt(x)) + (sqrt((t + 1.0d0)) - sqrt(t))
                                else if (t_1 <= 2.5d0) then
                                    tmp = (sqrt((1.0d0 + x)) + t_2) - (sqrt(x) + sqrt(y))
                                else
                                    tmp = ((1.0d0 + (t_2 + sqrt((1.0d0 + z)))) - 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((x + 1.0)) - Math.sqrt(x)) + (Math.sqrt((y + 1.0)) - Math.sqrt(y))) + (Math.sqrt((z + 1.0)) - Math.sqrt(z));
                            	double t_2 = Math.sqrt((1.0 + y));
                            	double tmp;
                            	if (t_1 <= 1.0) {
                            		tmp = ((1.0 + (0.5 * x)) - Math.sqrt(x)) + (Math.sqrt((t + 1.0)) - Math.sqrt(t));
                            	} else if (t_1 <= 2.5) {
                            		tmp = (Math.sqrt((1.0 + x)) + t_2) - (Math.sqrt(x) + Math.sqrt(y));
                            	} else {
                            		tmp = ((1.0 + (t_2 + Math.sqrt((1.0 + z)))) - 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((x + 1.0)) - math.sqrt(x)) + (math.sqrt((y + 1.0)) - math.sqrt(y))) + (math.sqrt((z + 1.0)) - math.sqrt(z))
                            	t_2 = math.sqrt((1.0 + y))
                            	tmp = 0
                            	if t_1 <= 1.0:
                            		tmp = ((1.0 + (0.5 * x)) - math.sqrt(x)) + (math.sqrt((t + 1.0)) - math.sqrt(t))
                            	elif t_1 <= 2.5:
                            		tmp = (math.sqrt((1.0 + x)) + t_2) - (math.sqrt(x) + math.sqrt(y))
                            	else:
                            		tmp = ((1.0 + (t_2 + math.sqrt((1.0 + z)))) - 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 = 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 = sqrt(Float64(1.0 + y))
                            	tmp = 0.0
                            	if (t_1 <= 1.0)
                            		tmp = Float64(Float64(Float64(1.0 + Float64(0.5 * x)) - sqrt(x)) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)));
                            	elseif (t_1 <= 2.5)
                            		tmp = Float64(Float64(sqrt(Float64(1.0 + x)) + t_2) - Float64(sqrt(x) + sqrt(y)));
                            	else
                            		tmp = Float64(Float64(Float64(1.0 + Float64(t_2 + sqrt(Float64(1.0 + z)))) - 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((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z));
                            	t_2 = sqrt((1.0 + y));
                            	tmp = 0.0;
                            	if (t_1 <= 1.0)
                            		tmp = ((1.0 + (0.5 * x)) - sqrt(x)) + (sqrt((t + 1.0)) - sqrt(t));
                            	elseif (t_1 <= 2.5)
                            		tmp = (sqrt((1.0 + x)) + t_2) - (sqrt(x) + sqrt(y));
                            	else
                            		tmp = ((1.0 + (t_2 + sqrt((1.0 + z)))) - 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[(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]}, Block[{t$95$2 = N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$1, 1.0], N[(N[(N[(1.0 + N[(0.5 * x), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$1, 2.5], N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + t$95$2), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(1.0 + N[(t$95$2 + N[Sqrt[N[(1.0 + z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $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 := \left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\\
                            t_2 := \sqrt{1 + y}\\
                            \mathbf{if}\;t\_1 \leq 1:\\
                            \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\
                            
                            \mathbf{elif}\;t\_1 \leq 2.5:\\
                            \;\;\;\;\left(\sqrt{1 + x} + t\_2\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
                            
                            \mathbf{else}:\\
                            \;\;\;\;\left(\left(1 + \left(t\_2 + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \sqrt{y}\\
                            
                            
                            \end{array}
                            \end{array}
                            
                            Derivation
                            1. Split input into 3 regimes
                            2. if (+.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))) < 1

                              1. Initial program 83.2%

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

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

                                  \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot x\right)\right)\right) - \color{blue}{\left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              5. Applied rewrites12.6%

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

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

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

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

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

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

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

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

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

                                  \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \frac{1}{2} \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                9. lift-sqrt.f6411.9

                                  \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + 0.5 \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              8. Applied rewrites11.9%

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

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

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

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

                                  \[\leadsto \left(\left(1 + \frac{1}{2} \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                4. lift-sqrt.f6433.3

                                  \[\leadsto \left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              11. Applied rewrites33.3%

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

                              if 1 < (+.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))) < 2.5

                              1. Initial program 95.4%

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

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

                                  \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                              5. Applied rewrites5.8%

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

                                \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                              7. 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.f6421.5

                                  \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                              8. Applied rewrites21.5%

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

                              if 2.5 < (+.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)))

                              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. Add Preprocessing
                              3. Taylor expanded in t around inf

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

                                  \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                              5. Applied rewrites51.9%

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

                                \[\leadsto \sqrt{z} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                              7. Step-by-step derivation
                                1. lift-sqrt.f642.2

                                  \[\leadsto \sqrt{z} - \left(\sqrt{z} + \sqrt{y}\right) \]
                              8. Applied rewrites2.2%

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

                                \[\leadsto \sqrt{z} - \sqrt{y} \]
                              10. Step-by-step derivation
                                1. lift-sqrt.f644.8

                                  \[\leadsto \sqrt{z} - \sqrt{y} \]
                              11. Applied rewrites4.8%

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

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

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

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

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

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

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

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

                                  \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \sqrt{y} \]
                                8. lift-sqrt.f6449.0

                                  \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \sqrt{y} \]
                              14. Applied rewrites49.0%

                                \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \sqrt{\color{blue}{y}} \]
                            3. Recombined 3 regimes into one program.
                            4. Final simplification30.2%

                              \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right) \leq 1:\\ \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{elif}\;\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right) \leq 2.5:\\ \;\;\;\;\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(1 + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \sqrt{y}\\ \end{array} \]
                            5. Add Preprocessing

                            Alternative 11: 94.1% accurate, 0.5× speedup?

                            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1}\\ t_2 := t\_1 - \sqrt{z}\\ t_3 := \sqrt{y + 1} - \sqrt{y}\\ t_4 := \sqrt{x + 1} - \sqrt{x}\\ t_5 := \sqrt{t + 1} - \sqrt{t}\\ \mathbf{if}\;\left(\left(t\_4 + t\_3\right) + t\_2\right) + t\_5 \leq 1.00005:\\ \;\;\;\;\left(\left(t\_4 + \frac{0.5 \cdot \sqrt{y}}{y}\right) + t\_2\right) + t\_5\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + \frac{1}{t\_1 + \sqrt{z}}\right) + t\_5\\ \end{array} \end{array} \]
                            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 (+ z 1.0)))
                                    (t_2 (- t_1 (sqrt z)))
                                    (t_3 (- (sqrt (+ y 1.0)) (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) 1.00005)
                                 (+ (+ (+ t_4 (/ (* 0.5 (sqrt y)) y)) t_2) t_5)
                                 (+ (+ (+ (- 1.0 (sqrt x)) t_3) (/ 1.0 (+ t_1 (sqrt z)))) t_5))))
                            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 = t_1 - sqrt(z);
                            	double t_3 = sqrt((y + 1.0)) - 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) <= 1.00005) {
                            		tmp = ((t_4 + ((0.5 * sqrt(y)) / y)) + t_2) + t_5;
                            	} else {
                            		tmp = (((1.0 - sqrt(x)) + t_3) + (1.0 / (t_1 + sqrt(z)))) + 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((z + 1.0d0))
                                t_2 = t_1 - sqrt(z)
                                t_3 = sqrt((y + 1.0d0)) - 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) <= 1.00005d0) then
                                    tmp = ((t_4 + ((0.5d0 * sqrt(y)) / y)) + t_2) + t_5
                                else
                                    tmp = (((1.0d0 - sqrt(x)) + t_3) + (1.0d0 / (t_1 + sqrt(z)))) + 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((z + 1.0));
                            	double t_2 = t_1 - Math.sqrt(z);
                            	double t_3 = Math.sqrt((y + 1.0)) - 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) <= 1.00005) {
                            		tmp = ((t_4 + ((0.5 * Math.sqrt(y)) / y)) + t_2) + t_5;
                            	} else {
                            		tmp = (((1.0 - Math.sqrt(x)) + t_3) + (1.0 / (t_1 + Math.sqrt(z)))) + t_5;
                            	}
                            	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 = t_1 - math.sqrt(z)
                            	t_3 = math.sqrt((y + 1.0)) - 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) <= 1.00005:
                            		tmp = ((t_4 + ((0.5 * math.sqrt(y)) / y)) + t_2) + t_5
                            	else:
                            		tmp = (((1.0 - math.sqrt(x)) + t_3) + (1.0 / (t_1 + math.sqrt(z)))) + t_5
                            	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(t_1 - sqrt(z))
                            	t_3 = Float64(sqrt(Float64(y + 1.0)) - 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) <= 1.00005)
                            		tmp = Float64(Float64(Float64(t_4 + Float64(Float64(0.5 * sqrt(y)) / y)) + t_2) + t_5);
                            	else
                            		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + t_3) + Float64(1.0 / Float64(t_1 + sqrt(z)))) + 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((z + 1.0));
                            	t_2 = t_1 - sqrt(z);
                            	t_3 = sqrt((y + 1.0)) - 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) <= 1.00005)
                            		tmp = ((t_4 + ((0.5 * sqrt(y)) / y)) + t_2) + t_5;
                            	else
                            		tmp = (((1.0 - sqrt(x)) + t_3) + (1.0 / (t_1 + sqrt(z)))) + 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[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(t$95$1 - N[Sqrt[z], $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[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], 1.00005], N[(N[(N[(t$95$4 + N[(N[(0.5 * N[Sqrt[y], $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$5), $MachinePrecision], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + N[(1.0 / N[(t$95$1 + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$5), $MachinePrecision]]]]]]]
                            
                            \begin{array}{l}
                            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                            \\
                            \begin{array}{l}
                            t_1 := \sqrt{z + 1}\\
                            t_2 := t\_1 - \sqrt{z}\\
                            t_3 := \sqrt{y + 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 1.00005:\\
                            \;\;\;\;\left(\left(t\_4 + \frac{0.5 \cdot \sqrt{y}}{y}\right) + t\_2\right) + t\_5\\
                            
                            \mathbf{else}:\\
                            \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + \frac{1}{t\_1 + \sqrt{z}}\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))) < 1.00005000000000011

                              1. Initial program 73.7%

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

                                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\frac{-1}{8} \cdot \sqrt{\frac{1}{y}} + \frac{1}{2} \cdot \sqrt{y}}{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              4. Step-by-step derivation
                                1. lower-/.f64N/A

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\frac{-1}{8} \cdot \sqrt{\frac{1}{y}} + \frac{1}{2} \cdot \sqrt{y}}{\color{blue}{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                2. *-commutativeN/A

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

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

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

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

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

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

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

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, \frac{-1}{8}, \frac{1}{2} \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                10. lift-sqrt.f6461.4

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, -0.125, 0.5 \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              5. Applied rewrites61.4%

                                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\mathsf{fma}\left({\left(\sqrt{y}\right)}^{-1}, -0.125, 0.5 \cdot \sqrt{y}\right)}{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              6. Taylor expanded in y around inf

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

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\frac{1}{2} \cdot \sqrt{y}}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                2. lift-*.f6462.3

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{0.5 \cdot \sqrt{y}}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              8. Applied rewrites62.3%

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

                              if 1.00005000000000011 < (+.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. Add Preprocessing
                              3. Step-by-step derivation
                                1. lift--.f64N/A

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

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

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

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

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

                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \color{blue}{\frac{\sqrt{z + 1} \cdot \sqrt{z + 1} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{z + 1} + \sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              4. Applied rewrites97.4%

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

                                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{\color{blue}{1}}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                              6. Step-by-step derivation
                                1. Applied rewrites97.9%

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

                                  \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                3. Step-by-step derivation
                                  1. Applied rewrites64.4%

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

                                Alternative 12: 93.0% accurate, 0.5× speedup?

                                \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ t_3 := \sqrt{y + 1} - \sqrt{y}\\ t_4 := \left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\\ \mathbf{if}\;\left(t\_4 + \left(t\_1 - \sqrt{z}\right)\right) + t\_2 \leq 1:\\ \;\;\;\;\left(t\_4 + \frac{1}{1 + \sqrt{z}}\right) + t\_2\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + \frac{1}{t\_1 + \sqrt{z}}\right) + t\_2\\ \end{array} \end{array} \]
                                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)))
                                        (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)))
                                   (if (<= (+ (+ t_4 (- t_1 (sqrt z))) t_2) 1.0)
                                     (+ (+ t_4 (/ 1.0 (+ 1.0 (sqrt z)))) t_2)
                                     (+ (+ (+ (- 1.0 (sqrt x)) t_3) (/ 1.0 (+ t_1 (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));
                                	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;
                                	double tmp;
                                	if (((t_4 + (t_1 - sqrt(z))) + t_2) <= 1.0) {
                                		tmp = (t_4 + (1.0 / (1.0 + sqrt(z)))) + t_2;
                                	} else {
                                		tmp = (((1.0 - sqrt(x)) + t_3) + (1.0 / (t_1 + sqrt(z)))) + 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) :: t_3
                                    real(8) :: t_4
                                    real(8) :: tmp
                                    t_1 = sqrt((z + 1.0d0))
                                    t_2 = sqrt((t + 1.0d0)) - sqrt(t)
                                    t_3 = sqrt((y + 1.0d0)) - sqrt(y)
                                    t_4 = (sqrt((x + 1.0d0)) - sqrt(x)) + t_3
                                    if (((t_4 + (t_1 - sqrt(z))) + t_2) <= 1.0d0) then
                                        tmp = (t_4 + (1.0d0 / (1.0d0 + sqrt(z)))) + t_2
                                    else
                                        tmp = (((1.0d0 - sqrt(x)) + t_3) + (1.0d0 / (t_1 + sqrt(z)))) + 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));
                                	double t_2 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
                                	double t_3 = Math.sqrt((y + 1.0)) - Math.sqrt(y);
                                	double t_4 = (Math.sqrt((x + 1.0)) - Math.sqrt(x)) + t_3;
                                	double tmp;
                                	if (((t_4 + (t_1 - Math.sqrt(z))) + t_2) <= 1.0) {
                                		tmp = (t_4 + (1.0 / (1.0 + Math.sqrt(z)))) + t_2;
                                	} else {
                                		tmp = (((1.0 - Math.sqrt(x)) + t_3) + (1.0 / (t_1 + Math.sqrt(z)))) + 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))
                                	t_2 = math.sqrt((t + 1.0)) - math.sqrt(t)
                                	t_3 = math.sqrt((y + 1.0)) - math.sqrt(y)
                                	t_4 = (math.sqrt((x + 1.0)) - math.sqrt(x)) + t_3
                                	tmp = 0
                                	if ((t_4 + (t_1 - math.sqrt(z))) + t_2) <= 1.0:
                                		tmp = (t_4 + (1.0 / (1.0 + math.sqrt(z)))) + t_2
                                	else:
                                		tmp = (((1.0 - math.sqrt(x)) + t_3) + (1.0 / (t_1 + math.sqrt(z)))) + t_2
                                	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 = Float64(sqrt(Float64(y + 1.0)) - sqrt(y))
                                	t_4 = Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + t_3)
                                	tmp = 0.0
                                	if (Float64(Float64(t_4 + Float64(t_1 - sqrt(z))) + t_2) <= 1.0)
                                		tmp = Float64(Float64(t_4 + Float64(1.0 / Float64(1.0 + sqrt(z)))) + t_2);
                                	else
                                		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + t_3) + Float64(1.0 / Float64(t_1 + sqrt(z)))) + 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));
                                	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;
                                	tmp = 0.0;
                                	if (((t_4 + (t_1 - sqrt(z))) + t_2) <= 1.0)
                                		tmp = (t_4 + (1.0 / (1.0 + sqrt(z)))) + t_2;
                                	else
                                		tmp = (((1.0 - sqrt(x)) + t_3) + (1.0 / (t_1 + sqrt(z)))) + 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[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[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision]}, If[LessEqual[N[(N[(t$95$4 + N[(t$95$1 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision], 1.0], N[(N[(t$95$4 + N[(1.0 / N[(1.0 + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + N[(1.0 / N[(t$95$1 + N[Sqrt[z], $MachinePrecision]), $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}\\
                                t_2 := \sqrt{t + 1} - \sqrt{t}\\
                                t_3 := \sqrt{y + 1} - \sqrt{y}\\
                                t_4 := \left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\\
                                \mathbf{if}\;\left(t\_4 + \left(t\_1 - \sqrt{z}\right)\right) + t\_2 \leq 1:\\
                                \;\;\;\;\left(t\_4 + \frac{1}{1 + \sqrt{z}}\right) + t\_2\\
                                
                                \mathbf{else}:\\
                                \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + \frac{1}{t\_1 + \sqrt{z}}\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

                                  1. Initial program 73.5%

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

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

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

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

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

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

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \color{blue}{\frac{\sqrt{z + 1} \cdot \sqrt{z + 1} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{z + 1} + \sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  4. Applied rewrites73.5%

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

                                    \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{\color{blue}{1}}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                  6. Step-by-step derivation
                                    1. Applied rewrites78.8%

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

                                      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\color{blue}{1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                    3. Step-by-step derivation
                                      1. Applied rewrites74.6%

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

                                      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)))

                                      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. Add Preprocessing
                                      3. Step-by-step derivation
                                        1. lift--.f64N/A

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

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

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

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

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

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

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

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

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

                                          \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                        3. Step-by-step derivation
                                          1. Applied rewrites63.0%

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

                                        Alternative 13: 97.1% accurate, 0.9× speedup?

                                        \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1} - \sqrt{y}\\ t_2 := \frac{1}{\sqrt{z + 1} + \sqrt{z}}\\ t_3 := \sqrt{t + 1} - \sqrt{t}\\ \mathbf{if}\;x \leq 30000000:\\ \;\;\;\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_1\right) + t\_2\right) + t\_3\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\frac{0.5 \cdot \sqrt{x}}{x} + t\_1\right) + t\_2\right) + t\_3\\ \end{array} \end{array} \]
                                        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)) (sqrt y)))
                                                (t_2 (/ 1.0 (+ (sqrt (+ z 1.0)) (sqrt z))))
                                                (t_3 (- (sqrt (+ t 1.0)) (sqrt t))))
                                           (if (<= x 30000000.0)
                                             (+ (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) t_1) t_2) t_3)
                                             (+ (+ (+ (/ (* 0.5 (sqrt x)) x) t_1) 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)) - sqrt(y);
                                        	double t_2 = 1.0 / (sqrt((z + 1.0)) + sqrt(z));
                                        	double t_3 = sqrt((t + 1.0)) - sqrt(t);
                                        	double tmp;
                                        	if (x <= 30000000.0) {
                                        		tmp = (((sqrt((x + 1.0)) - sqrt(x)) + t_1) + t_2) + t_3;
                                        	} else {
                                        		tmp = ((((0.5 * sqrt(x)) / x) + t_1) + 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) :: tmp
                                            t_1 = sqrt((y + 1.0d0)) - sqrt(y)
                                            t_2 = 1.0d0 / (sqrt((z + 1.0d0)) + sqrt(z))
                                            t_3 = sqrt((t + 1.0d0)) - sqrt(t)
                                            if (x <= 30000000.0d0) then
                                                tmp = (((sqrt((x + 1.0d0)) - sqrt(x)) + t_1) + t_2) + t_3
                                            else
                                                tmp = ((((0.5d0 * sqrt(x)) / x) + t_1) + 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)) - Math.sqrt(y);
                                        	double t_2 = 1.0 / (Math.sqrt((z + 1.0)) + Math.sqrt(z));
                                        	double t_3 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
                                        	double tmp;
                                        	if (x <= 30000000.0) {
                                        		tmp = (((Math.sqrt((x + 1.0)) - Math.sqrt(x)) + t_1) + t_2) + t_3;
                                        	} else {
                                        		tmp = ((((0.5 * Math.sqrt(x)) / x) + t_1) + 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)) - math.sqrt(y)
                                        	t_2 = 1.0 / (math.sqrt((z + 1.0)) + math.sqrt(z))
                                        	t_3 = math.sqrt((t + 1.0)) - math.sqrt(t)
                                        	tmp = 0
                                        	if x <= 30000000.0:
                                        		tmp = (((math.sqrt((x + 1.0)) - math.sqrt(x)) + t_1) + t_2) + t_3
                                        	else:
                                        		tmp = ((((0.5 * math.sqrt(x)) / x) + t_1) + t_2) + t_3
                                        	return tmp
                                        
                                        x, y, z, t = sort([x, y, z, t])
                                        function code(x, y, z, t)
                                        	t_1 = Float64(sqrt(Float64(y + 1.0)) - sqrt(y))
                                        	t_2 = Float64(1.0 / Float64(sqrt(Float64(z + 1.0)) + sqrt(z)))
                                        	t_3 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
                                        	tmp = 0.0
                                        	if (x <= 30000000.0)
                                        		tmp = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + t_1) + t_2) + t_3);
                                        	else
                                        		tmp = Float64(Float64(Float64(Float64(Float64(0.5 * sqrt(x)) / x) + t_1) + 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)) - sqrt(y);
                                        	t_2 = 1.0 / (sqrt((z + 1.0)) + sqrt(z));
                                        	t_3 = sqrt((t + 1.0)) - sqrt(t);
                                        	tmp = 0.0;
                                        	if (x <= 30000000.0)
                                        		tmp = (((sqrt((x + 1.0)) - sqrt(x)) + t_1) + t_2) + t_3;
                                        	else
                                        		tmp = ((((0.5 * sqrt(x)) / x) + t_1) + 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[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(1.0 / N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 30000000.0], N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$3), $MachinePrecision], N[(N[(N[(N[(N[(0.5 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] + t$95$1), $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} - \sqrt{y}\\
                                        t_2 := \frac{1}{\sqrt{z + 1} + \sqrt{z}}\\
                                        t_3 := \sqrt{t + 1} - \sqrt{t}\\
                                        \mathbf{if}\;x \leq 30000000:\\
                                        \;\;\;\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_1\right) + t\_2\right) + t\_3\\
                                        
                                        \mathbf{else}:\\
                                        \;\;\;\;\left(\left(\frac{0.5 \cdot \sqrt{x}}{x} + t\_1\right) + t\_2\right) + t\_3\\
                                        
                                        
                                        \end{array}
                                        \end{array}
                                        
                                        Derivation
                                        1. Split input into 2 regimes
                                        2. if x < 3e7

                                          1. Initial program 97.6%

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

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

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

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

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

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

                                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \color{blue}{\frac{\sqrt{z + 1} \cdot \sqrt{z + 1} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{z + 1} + \sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                          4. Applied rewrites97.6%

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

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

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

                                            if 3e7 < x

                                            1. Initial program 81.4%

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

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

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

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

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

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

                                                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \color{blue}{\frac{\sqrt{z + 1} \cdot \sqrt{z + 1} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{z + 1} + \sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            4. Applied rewrites81.6%

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

                                              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{\color{blue}{1}}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            6. Step-by-step derivation
                                              1. Applied rewrites85.0%

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

                                                \[\leadsto \left(\left(\color{blue}{\frac{\frac{-1}{8} \cdot \sqrt{\frac{1}{x}} + \frac{1}{2} \cdot \sqrt{x}}{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              3. Step-by-step derivation
                                                1. lower-/.f64N/A

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

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

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

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

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

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

                                                  \[\leadsto \left(\left(\frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{x}}, \frac{1}{2} \cdot \sqrt{x}\right)}{x} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                8. lift-sqrt.f6492.8

                                                  \[\leadsto \left(\left(\frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{x}}, 0.5 \cdot \sqrt{x}\right)}{x} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              4. Applied rewrites92.8%

                                                \[\leadsto \left(\left(\color{blue}{\frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{x}}, 0.5 \cdot \sqrt{x}\right)}{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              5. Taylor expanded in x around inf

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

                                                  \[\leadsto \left(\left(\frac{\frac{1}{2} \cdot \sqrt{x}}{x} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                2. lift-*.f6492.8

                                                  \[\leadsto \left(\left(\frac{0.5 \cdot \sqrt{x}}{x} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              7. Applied rewrites92.8%

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

                                            Alternative 14: 96.1% accurate, 0.9× speedup?

                                            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \left(\left(\frac{1}{\sqrt{1 + x} + \sqrt{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \end{array} \]
                                            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                            (FPCore (x y z t)
                                             :precision binary64
                                             (+
                                              (+
                                               (+ (/ 1.0 (+ (sqrt (+ 1.0 x)) (sqrt x))) (- (sqrt (+ y 1.0)) (sqrt y)))
                                               (- (sqrt (+ z 1.0)) (sqrt z)))
                                              (- (sqrt (+ t 1.0)) (sqrt t))))
                                            assert(x < y && y < z && z < t);
                                            double code(double x, double y, double z, double t) {
                                            	return (((1.0 / (sqrt((1.0 + x)) + sqrt(x))) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
                                            }
                                            
                                            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 = (((1.0d0 / (sqrt((1.0d0 + x)) + sqrt(x))) + (sqrt((y + 1.0d0)) - sqrt(y))) + (sqrt((z + 1.0d0)) - sqrt(z))) + (sqrt((t + 1.0d0)) - sqrt(t))
                                            end function
                                            
                                            assert x < y && y < z && z < t;
                                            public static double code(double x, double y, double z, double t) {
                                            	return (((1.0 / (Math.sqrt((1.0 + x)) + 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));
                                            }
                                            
                                            [x, y, z, t] = sort([x, y, z, t])
                                            def code(x, y, z, t):
                                            	return (((1.0 / (math.sqrt((1.0 + x)) + 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))
                                            
                                            x, y, z, t = sort([x, y, z, t])
                                            function code(x, y, z, t)
                                            	return Float64(Float64(Float64(Float64(1.0 / Float64(sqrt(Float64(1.0 + x)) + 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
                                            
                                            x, y, z, t = num2cell(sort([x, y, z, t])){:}
                                            function tmp = code(x, y, z, t)
                                            	tmp = (((1.0 / (sqrt((1.0 + x)) + sqrt(x))) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
                                            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[(N[(1.0 / N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[Sqrt[x], $MachinePrecision]), $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}
                                            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                            \\
                                            \left(\left(\frac{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)
                                            \end{array}
                                            
                                            Derivation
                                            1. Initial program 90.0%

                                              \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            2. Add Preprocessing
                                            3. 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

                                                \[\leadsto \left(\left(\color{blue}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{1 + x} + \sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            4. Applied rewrites90.1%

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

                                              \[\leadsto \left(\left(\frac{\color{blue}{1}}{\sqrt{1 + x} + \sqrt{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                            6. Step-by-step derivation
                                              1. Applied rewrites93.7%

                                                \[\leadsto \left(\left(\frac{\color{blue}{1}}{\sqrt{1 + x} + \sqrt{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              2. Final simplification93.7%

                                                \[\leadsto \left(\left(\frac{1}{\sqrt{1 + x} + \sqrt{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              3. Add Preprocessing

                                              Alternative 15: 91.6% accurate, 1.0× speedup?

                                              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \left(\left(\left(1 - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \end{array} \]
                                              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                              (FPCore (x y z t)
                                               :precision binary64
                                               (+
                                                (+
                                                 (+ (- 1.0 (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
                                                 (/ 1.0 (+ (sqrt (+ z 1.0)) (sqrt z))))
                                                (- (sqrt (+ t 1.0)) (sqrt t))))
                                              assert(x < y && y < z && z < t);
                                              double code(double x, double y, double z, double t) {
                                              	return (((1.0 - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (1.0 / (sqrt((z + 1.0)) + sqrt(z)))) + (sqrt((t + 1.0)) - sqrt(t));
                                              }
                                              
                                              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 = (((1.0d0 - sqrt(x)) + (sqrt((y + 1.0d0)) - sqrt(y))) + (1.0d0 / (sqrt((z + 1.0d0)) + sqrt(z)))) + (sqrt((t + 1.0d0)) - sqrt(t))
                                              end function
                                              
                                              assert x < y && y < z && z < t;
                                              public static double code(double x, double y, double z, double t) {
                                              	return (((1.0 - Math.sqrt(x)) + (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));
                                              }
                                              
                                              [x, y, z, t] = sort([x, y, z, t])
                                              def code(x, y, z, t):
                                              	return (((1.0 - math.sqrt(x)) + (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))
                                              
                                              x, y, z, t = sort([x, y, z, t])
                                              function code(x, y, z, t)
                                              	return Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + 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
                                              
                                              x, y, z, t = num2cell(sort([x, y, z, t])){:}
                                              function tmp = code(x, y, z, t)
                                              	tmp = (((1.0 - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (1.0 / (sqrt((z + 1.0)) + sqrt(z)))) + (sqrt((t + 1.0)) - sqrt(t));
                                              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[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $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}
                                              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                              \\
                                              \left(\left(\left(1 - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)
                                              \end{array}
                                              
                                              Derivation
                                              1. Initial program 90.0%

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

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

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

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

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

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

                                                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \color{blue}{\frac{\sqrt{z + 1} \cdot \sqrt{z + 1} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{z + 1} + \sqrt{z}}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              4. Applied rewrites90.1%

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

                                                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{\color{blue}{1}}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                              6. Step-by-step derivation
                                                1. Applied rewrites92.0%

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

                                                  \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                3. Step-by-step derivation
                                                  1. Applied rewrites51.3%

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

                                                  Alternative 16: 91.1% accurate, 1.1× speedup?

                                                  \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \end{array} \]
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  (FPCore (x y z t)
                                                   :precision binary64
                                                   (+
                                                    (+
                                                     (+ (- (fma 0.5 x 1.0) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
                                                     (- (sqrt (+ z 1.0)) (sqrt z)))
                                                    (- (sqrt (+ t 1.0)) (sqrt t))))
                                                  assert(x < y && y < z && z < t);
                                                  double code(double x, double y, double z, double t) {
                                                  	return (((fma(0.5, x, 1.0) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
                                                  }
                                                  
                                                  x, y, z, t = sort([x, y, z, t])
                                                  function code(x, y, z, t)
                                                  	return Float64(Float64(Float64(Float64(fma(0.5, 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
                                                  
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  code[x_, y_, z_, t_] := N[(N[(N[(N[(N[(0.5 * x + 1.0), $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}
                                                  [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                                  \\
                                                  \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{t + 1} - \sqrt{t}\right)
                                                  \end{array}
                                                  
                                                  Derivation
                                                  1. Initial program 90.0%

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

                                                    \[\leadsto \left(\left(\left(\color{blue}{\left(1 + \frac{1}{2} \cdot x\right)} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  4. 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.f6453.3

                                                      \[\leadsto \left(\left(\left(\mathsf{fma}\left(0.5, \color{blue}{x}, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  5. Applied rewrites53.3%

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

                                                  Alternative 17: 90.5% accurate, 1.1× speedup?

                                                  \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \left(\left(\left(1 - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \end{array} \]
                                                  NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                  (FPCore (x y z t)
                                                   :precision binary64
                                                   (+
                                                    (+
                                                     (+ (- 1.0 (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
                                                     (- (sqrt (+ z 1.0)) (sqrt z)))
                                                    (- (sqrt (+ t 1.0)) (sqrt t))))
                                                  assert(x < y && y < z && z < t);
                                                  double code(double x, double y, double z, double t) {
                                                  	return (((1.0 - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
                                                  }
                                                  
                                                  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 = (((1.0d0 - sqrt(x)) + (sqrt((y + 1.0d0)) - sqrt(y))) + (sqrt((z + 1.0d0)) - sqrt(z))) + (sqrt((t + 1.0d0)) - sqrt(t))
                                                  end function
                                                  
                                                  assert x < y && y < z && z < t;
                                                  public static double code(double x, double y, double z, double t) {
                                                  	return (((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));
                                                  }
                                                  
                                                  [x, y, z, t] = sort([x, y, z, t])
                                                  def code(x, y, z, t):
                                                  	return (((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))
                                                  
                                                  x, y, z, t = sort([x, y, z, t])
                                                  function code(x, y, z, t)
                                                  	return Float64(Float64(Float64(Float64(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
                                                  
                                                  x, y, z, t = num2cell(sort([x, y, z, t])){:}
                                                  function tmp = code(x, y, z, t)
                                                  	tmp = (((1.0 - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
                                                  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[(N[(1.0 - 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}
                                                  [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
                                                  \\
                                                  \left(\left(\left(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}
                                                  
                                                  Derivation
                                                  1. Initial program 90.0%

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

                                                    \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                  4. Step-by-step derivation
                                                    1. Applied rewrites51.0%

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

                                                    Alternative 18: 64.9% accurate, 1.8× speedup?

                                                    \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} \mathbf{if}\;y \leq 4 \cdot 10^{+18}:\\ \;\;\;\;\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \end{array} \end{array} \]
                                                    NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                    (FPCore (x y z t)
                                                     :precision binary64
                                                     (if (<= y 4e+18)
                                                       (- (+ (sqrt (+ 1.0 x)) (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                                                       (+ (- (+ 1.0 (* 0.5 x)) (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 tmp;
                                                    	if (y <= 4e+18) {
                                                    		tmp = (sqrt((1.0 + x)) + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                                                    	} else {
                                                    		tmp = ((1.0 + (0.5 * x)) - 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) :: tmp
                                                        if (y <= 4d+18) then
                                                            tmp = (sqrt((1.0d0 + x)) + sqrt((1.0d0 + y))) - (sqrt(x) + sqrt(y))
                                                        else
                                                            tmp = ((1.0d0 + (0.5d0 * x)) - 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 tmp;
                                                    	if (y <= 4e+18) {
                                                    		tmp = (Math.sqrt((1.0 + x)) + Math.sqrt((1.0 + y))) - (Math.sqrt(x) + Math.sqrt(y));
                                                    	} else {
                                                    		tmp = ((1.0 + (0.5 * x)) - 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):
                                                    	tmp = 0
                                                    	if y <= 4e+18:
                                                    		tmp = (math.sqrt((1.0 + x)) + math.sqrt((1.0 + y))) - (math.sqrt(x) + math.sqrt(y))
                                                    	else:
                                                    		tmp = ((1.0 + (0.5 * x)) - 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)
                                                    	tmp = 0.0
                                                    	if (y <= 4e+18)
                                                    		tmp = Float64(Float64(sqrt(Float64(1.0 + x)) + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
                                                    	else
                                                    		tmp = Float64(Float64(Float64(1.0 + Float64(0.5 * x)) - 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)
                                                    	tmp = 0.0;
                                                    	if (y <= 4e+18)
                                                    		tmp = (sqrt((1.0 + x)) + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
                                                    	else
                                                    		tmp = ((1.0 + (0.5 * x)) - 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_] := If[LessEqual[y, 4e+18], 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], N[(N[(N[(1.0 + N[(0.5 * x), $MachinePrecision]), $MachinePrecision] - 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}
                                                    \mathbf{if}\;y \leq 4 \cdot 10^{+18}:\\
                                                    \;\;\;\;\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
                                                    
                                                    \mathbf{else}:\\
                                                    \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\
                                                    
                                                    
                                                    \end{array}
                                                    \end{array}
                                                    
                                                    Derivation
                                                    1. Split input into 2 regimes
                                                    2. if y < 4e18

                                                      1. Initial program 95.6%

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

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

                                                          \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                      5. Applied rewrites15.9%

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

                                                        \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \color{blue}{\left(\sqrt{x} + \sqrt{y}\right)} \]
                                                      7. 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.f6422.4

                                                          \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                                                      8. Applied rewrites22.4%

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

                                                      if 4e18 < y

                                                      1. Initial program 84.6%

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

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

                                                          \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot x\right)\right)\right) - \color{blue}{\left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      5. Applied rewrites13.7%

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

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

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

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

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

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

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

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

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

                                                          \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \frac{1}{2} \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                        9. lift-sqrt.f6413.1

                                                          \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + 0.5 \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      8. Applied rewrites13.1%

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

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

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

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

                                                          \[\leadsto \left(\left(1 + \frac{1}{2} \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                        4. lift-sqrt.f6436.0

                                                          \[\leadsto \left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      11. Applied rewrites36.0%

                                                        \[\leadsto \left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    3. Recombined 2 regimes into one program.
                                                    4. Final simplification29.3%

                                                      \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq 4 \cdot 10^{+18}:\\ \;\;\;\;\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \end{array} \]
                                                    5. Add Preprocessing

                                                    Alternative 19: 35.1% accurate, 2.2× speedup?

                                                    \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \end{array} \]
                                                    NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
                                                    (FPCore (x y z t)
                                                     :precision binary64
                                                     (+ (- (+ 1.0 (* 0.5 x)) (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) {
                                                    	return ((1.0 + (0.5 * x)) - sqrt(x)) + (sqrt((t + 1.0)) - sqrt(t));
                                                    }
                                                    
                                                    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 = ((1.0d0 + (0.5d0 * x)) - sqrt(x)) + (sqrt((t + 1.0d0)) - sqrt(t))
                                                    end function
                                                    
                                                    assert x < y && y < z && z < t;
                                                    public static double code(double x, double y, double z, double t) {
                                                    	return ((1.0 + (0.5 * x)) - Math.sqrt(x)) + (Math.sqrt((t + 1.0)) - Math.sqrt(t));
                                                    }
                                                    
                                                    [x, y, z, t] = sort([x, y, z, t])
                                                    def code(x, y, z, t):
                                                    	return ((1.0 + (0.5 * x)) - math.sqrt(x)) + (math.sqrt((t + 1.0)) - math.sqrt(t))
                                                    
                                                    x, y, z, t = sort([x, y, z, t])
                                                    function code(x, y, z, t)
                                                    	return Float64(Float64(Float64(1.0 + Float64(0.5 * x)) - sqrt(x)) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)))
                                                    end
                                                    
                                                    x, y, z, t = num2cell(sort([x, y, z, t])){:}
                                                    function tmp = code(x, y, z, t)
                                                    	tmp = ((1.0 + (0.5 * x)) - sqrt(x)) + (sqrt((t + 1.0)) - sqrt(t));
                                                    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[(1.0 + N[(0.5 * x), $MachinePrecision]), $MachinePrecision] - 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])\\
                                                    \\
                                                    \left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)
                                                    \end{array}
                                                    
                                                    Derivation
                                                    1. Initial program 90.0%

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

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

                                                        \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot x\right)\right)\right) - \color{blue}{\left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    5. Applied rewrites21.3%

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

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

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

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

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

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

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

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

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

                                                        \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + \frac{1}{2} \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      9. lift-sqrt.f6422.5

                                                        \[\leadsto \left(\left(1 + \left(\sqrt{1 + y} + 0.5 \cdot x\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    8. Applied rewrites22.5%

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

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

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

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

                                                        \[\leadsto \left(\left(1 + \frac{1}{2} \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                      4. lift-sqrt.f6424.3

                                                        \[\leadsto \left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    11. Applied rewrites24.3%

                                                      \[\leadsto \left(\left(1 + 0.5 \cdot x\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                                                    12. 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 90.0%

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

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

                                                        \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                    5. Applied rewrites9.4%

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

                                                      \[\leadsto \sqrt{z} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                                                    7. Step-by-step derivation
                                                      1. lift-sqrt.f642.2

                                                        \[\leadsto \sqrt{z} - \left(\sqrt{z} + \sqrt{y}\right) \]
                                                    8. Applied rewrites2.2%

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

                                                      \[\leadsto \sqrt{z} - \sqrt{y} \]
                                                    10. Step-by-step derivation
                                                      1. lift-sqrt.f644.1

                                                        \[\leadsto \sqrt{z} - \sqrt{y} \]
                                                    11. Applied rewrites4.1%

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

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

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

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

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

                                                        \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \]
                                                      5. lower-+.f6411.5

                                                        \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \]
                                                    14. Applied rewrites11.5%

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

                                                    Alternative 21: 7.7% 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 90.0%

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

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

                                                        \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                                                    5. Applied rewrites9.4%

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

                                                      \[\leadsto \sqrt{z} - \left(\color{blue}{\sqrt{z}} + \sqrt{y}\right) \]
                                                    7. Step-by-step derivation
                                                      1. lift-sqrt.f642.2

                                                        \[\leadsto \sqrt{z} - \left(\sqrt{z} + \sqrt{y}\right) \]
                                                    8. Applied rewrites2.2%

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

                                                      \[\leadsto \sqrt{z} - \sqrt{y} \]
                                                    10. Step-by-step derivation
                                                      1. lift-sqrt.f644.1

                                                        \[\leadsto \sqrt{z} - \sqrt{y} \]
                                                    11. Applied rewrites4.1%

                                                      \[\leadsto \sqrt{z} - \sqrt{y} \]
                                                    12. 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 2025080 
                                                    (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))))