Main:z from

Percentage Accurate: 91.9% → 97.2%
Time: 13.5s
Alternatives: 19
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}

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 19 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: 91.9% 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: 97.2% accurate, 0.9× speedup?

\[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1} - \sqrt{z}\\ t_2 := \frac{1}{\sqrt{y} + \sqrt{1 + y}}\\ \mathbf{if}\;x \leq 0.445:\\ \;\;\;\;\left(\left(\left(1 + t\_2\right) - \sqrt{x}\right) + t\_1\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\mathsf{fma}\left(0.5, \frac{1}{\sqrt{x}}, t\_2\right) + t\_1\right) + \left(\sqrt{t} - \sqrt{t}\right)\\ \end{array} \end{array} \]
NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
(FPCore (x y z t)
 :precision binary64
 (let* ((t_1 (- (sqrt (+ z 1.0)) (sqrt z)))
        (t_2 (/ 1.0 (+ (sqrt y) (sqrt (+ 1.0 y))))))
   (if (<= x 0.445)
     (+ (+ (- (+ 1.0 t_2) (sqrt x)) t_1) (- (sqrt (+ t 1.0)) (sqrt t)))
     (+ (+ (fma 0.5 (/ 1.0 (sqrt x)) t_2) t_1) (- (sqrt t) (sqrt t))))))
assert(x < y && y < z && z < t);
double code(double x, double y, double z, double t) {
	double t_1 = sqrt((z + 1.0)) - sqrt(z);
	double t_2 = 1.0 / (sqrt(y) + sqrt((1.0 + y)));
	double tmp;
	if (x <= 0.445) {
		tmp = (((1.0 + t_2) - sqrt(x)) + t_1) + (sqrt((t + 1.0)) - sqrt(t));
	} else {
		tmp = (fma(0.5, (1.0 / sqrt(x)), t_2) + t_1) + (sqrt(t) - sqrt(t));
	}
	return tmp;
}
x, y, z, t = sort([x, y, z, t])
function code(x, y, z, t)
	t_1 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
	t_2 = Float64(1.0 / Float64(sqrt(y) + sqrt(Float64(1.0 + y))))
	tmp = 0.0
	if (x <= 0.445)
		tmp = Float64(Float64(Float64(Float64(1.0 + t_2) - sqrt(x)) + t_1) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)));
	else
		tmp = Float64(Float64(fma(0.5, Float64(1.0 / sqrt(x)), t_2) + t_1) + Float64(sqrt(t) - sqrt(t)));
	end
	return tmp
end
NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(1.0 / N[(N[Sqrt[y], $MachinePrecision] + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 0.445], N[(N[(N[(N[(1.0 + t$95$2), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(0.5 * N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$1), $MachinePrecision] + N[(N[Sqrt[t], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}
[x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
\\
\begin{array}{l}
t_1 := \sqrt{z + 1} - \sqrt{z}\\
t_2 := \frac{1}{\sqrt{y} + \sqrt{1 + y}}\\
\mathbf{if}\;x \leq 0.445:\\
\;\;\;\;\left(\left(\left(1 + t\_2\right) - \sqrt{x}\right) + t\_1\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 0.445000000000000007

    1. Initial program 97.0%

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

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

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

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

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

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

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

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
    3. Applied rewrites97.2%

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

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

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

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

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

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

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

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

        \[\leadsto \left(\left(\left(1 + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      8. lift-sqrt.f6497.6

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

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

    if 0.445000000000000007 < x

    1. Initial program 13.8%

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

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

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

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

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

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

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

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
    3. Applied rewrites13.9%

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

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

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

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

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

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

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

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{y}}, \frac{1}{2} \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      8. lift-sqrt.f6419.3

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{y}}, 0.5 \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
    6. Applied rewrites19.3%

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

      \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{y}}, \frac{1}{2} \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{\color{blue}{t}} - \sqrt{t}\right) \]
    8. Step-by-step derivation
      1. Applied rewrites19.3%

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

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

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

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

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

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

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

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

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

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

          \[\leadsto \left(\mathsf{fma}\left(\frac{1}{2}, \frac{1}{\sqrt{x}}, \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t} - \sqrt{t}\right) \]
        10. lower-+.f6490.8

          \[\leadsto \left(\mathsf{fma}\left(0.5, \frac{1}{\sqrt{x}}, \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t} - \sqrt{t}\right) \]
      4. Applied rewrites90.8%

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

    Alternative 2: 97.2% accurate, 0.8× speedup?

    \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1} - \sqrt{z}\\ \mathbf{if}\;x \leq 2.8:\\ \;\;\;\;\left(\left(\left(1 + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) - \sqrt{x}\right) + t\_1\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + \frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{y}}, 0.5 \cdot \sqrt{y}\right)}{y}\right) + t\_1\right) + \left(\sqrt{t} - \sqrt{t}\right)\\ \end{array} \end{array} \]
    NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
    (FPCore (x y z t)
     :precision binary64
     (let* ((t_1 (- (sqrt (+ z 1.0)) (sqrt z))))
       (if (<= x 2.8)
         (+
          (+ (- (+ 1.0 (/ 1.0 (+ (sqrt y) (sqrt (+ 1.0 y))))) (sqrt x)) t_1)
          (- (sqrt (+ t 1.0)) (sqrt t)))
         (+
          (+
           (+
            (* 0.5 (/ 1.0 (sqrt x)))
            (/ (fma -0.125 (/ 1.0 (sqrt y)) (* 0.5 (sqrt y))) y))
           t_1)
          (- (sqrt t) (sqrt t))))))
    assert(x < y && y < z && z < t);
    double code(double x, double y, double z, double t) {
    	double t_1 = sqrt((z + 1.0)) - sqrt(z);
    	double tmp;
    	if (x <= 2.8) {
    		tmp = (((1.0 + (1.0 / (sqrt(y) + sqrt((1.0 + y))))) - sqrt(x)) + t_1) + (sqrt((t + 1.0)) - sqrt(t));
    	} else {
    		tmp = (((0.5 * (1.0 / sqrt(x))) + (fma(-0.125, (1.0 / sqrt(y)), (0.5 * sqrt(y))) / y)) + t_1) + (sqrt(t) - sqrt(t));
    	}
    	return tmp;
    }
    
    x, y, z, t = sort([x, y, z, t])
    function code(x, y, z, t)
    	t_1 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
    	tmp = 0.0
    	if (x <= 2.8)
    		tmp = Float64(Float64(Float64(Float64(1.0 + Float64(1.0 / Float64(sqrt(y) + sqrt(Float64(1.0 + y))))) - sqrt(x)) + t_1) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)));
    	else
    		tmp = Float64(Float64(Float64(Float64(0.5 * Float64(1.0 / sqrt(x))) + Float64(fma(-0.125, Float64(1.0 / sqrt(y)), Float64(0.5 * sqrt(y))) / y)) + t_1) + Float64(sqrt(t) - sqrt(t)));
    	end
    	return tmp
    end
    
    NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
    code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 2.8], N[(N[(N[(N[(1.0 + N[(1.0 / N[(N[Sqrt[y], $MachinePrecision] + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(0.5 * N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(-0.125 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision] + N[(0.5 * N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + N[(N[Sqrt[t], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
    
    \begin{array}{l}
    [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
    \\
    \begin{array}{l}
    t_1 := \sqrt{z + 1} - \sqrt{z}\\
    \mathbf{if}\;x \leq 2.8:\\
    \;\;\;\;\left(\left(\left(1 + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) - \sqrt{x}\right) + t\_1\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;\left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + \frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{y}}, 0.5 \cdot \sqrt{y}\right)}{y}\right) + t\_1\right) + \left(\sqrt{t} - \sqrt{t}\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if x < 2.7999999999999998

      1. Initial program 97.0%

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

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

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

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

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

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

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

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      3. Applied rewrites97.2%

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

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

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

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

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

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

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

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

          \[\leadsto \left(\left(\left(1 + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        8. lift-sqrt.f6497.5

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

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

      if 2.7999999999999998 < x

      1. Initial program 13.5%

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

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

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

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

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

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

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

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      3. Applied rewrites13.6%

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

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

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

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

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

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

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

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{y}}, \frac{1}{2} \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        8. lift-sqrt.f6419.0

          \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{y}}, 0.5 \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
      6. Applied rewrites19.0%

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

        \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{y}}, \frac{1}{2} \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{\color{blue}{t}} - \sqrt{t}\right) \]
      8. Step-by-step derivation
        1. Applied rewrites19.0%

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

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

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

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

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

            \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{x}}} + \frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{y}}, \frac{1}{2} \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t} - \sqrt{t}\right) \]
          5. lift-sqrt.f6491.1

            \[\leadsto \left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + \frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{y}}, 0.5 \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t} - \sqrt{t}\right) \]
        4. Applied rewrites91.1%

          \[\leadsto \left(\left(\color{blue}{0.5 \cdot \frac{1}{\sqrt{x}}} + \frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{y}}, 0.5 \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t} - \sqrt{t}\right) \]
      9. Recombined 2 regimes into one program.
      10. Add Preprocessing

      Alternative 3: 96.3% accurate, 0.9× speedup?

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

        1. Initial program 97.0%

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

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

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

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

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

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

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

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        3. Applied rewrites97.2%

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

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

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

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

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

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

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

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

            \[\leadsto \left(\left(\left(1 + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) - \sqrt{x}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          8. lift-sqrt.f6497.6

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

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

        if 1 < x

        1. Initial program 13.6%

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

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

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

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

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

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

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z}} \cdot \frac{1}{2}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          6. lift-sqrt.f6416.7

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z}} \cdot 0.5\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        4. Applied rewrites16.7%

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

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

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

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

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

            \[\leadsto \left(\left(\frac{1}{2} \cdot \frac{1}{\color{blue}{\sqrt{x}}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z}} \cdot \frac{1}{2}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          5. lift-sqrt.f6476.9

            \[\leadsto \left(\left(0.5 \cdot \frac{1}{\sqrt{x}} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \frac{1}{\sqrt{z}} \cdot 0.5\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        7. Applied rewrites76.9%

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

      Alternative 4: 93.8% accurate, 0.3× speedup?

      \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{1 + x}\\ t_2 := \sqrt{z + 1} - \sqrt{z}\\ t_3 := \sqrt{t + 1} - \sqrt{t}\\ t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + t\_2\right) + t\_3\\ t_5 := 0.5 \cdot \frac{1}{\sqrt{z}}\\ \mathbf{if}\;t\_4 \leq 1.0001:\\ \;\;\;\;\left(t\_1 + \mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, t\_5\right)\right) - \sqrt{x}\\ \mathbf{elif}\;t\_4 \leq 2.0001:\\ \;\;\;\;\left(t\_1 + \left(\sqrt{1 + y} + t\_5\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + \left(1 - \sqrt{y}\right)\right) + t\_2\right) + t\_3\\ \end{array} \end{array} \]
      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 (+ 1.0 x)))
              (t_2 (- (sqrt (+ z 1.0)) (sqrt z)))
              (t_3 (- (sqrt (+ t 1.0)) (sqrt t)))
              (t_4
               (+
                (+
                 (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
                 t_2)
                t_3))
              (t_5 (* 0.5 (/ 1.0 (sqrt z)))))
         (if (<= t_4 1.0001)
           (- (+ t_1 (fma 0.5 (/ 1.0 (sqrt y)) t_5)) (sqrt x))
           (if (<= t_4 2.0001)
             (- (+ t_1 (+ (sqrt (+ 1.0 y)) t_5)) (+ (sqrt x) (sqrt y)))
             (+ (+ (+ (- (fma 0.5 x 1.0) (sqrt x)) (- 1.0 (sqrt y))) t_2) t_3)))))
      assert(x < y && y < z && z < t);
      double code(double x, double y, double z, double t) {
      	double t_1 = sqrt((1.0 + x));
      	double t_2 = sqrt((z + 1.0)) - sqrt(z);
      	double t_3 = sqrt((t + 1.0)) - sqrt(t);
      	double t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + t_2) + t_3;
      	double t_5 = 0.5 * (1.0 / sqrt(z));
      	double tmp;
      	if (t_4 <= 1.0001) {
      		tmp = (t_1 + fma(0.5, (1.0 / sqrt(y)), t_5)) - sqrt(x);
      	} else if (t_4 <= 2.0001) {
      		tmp = (t_1 + (sqrt((1.0 + y)) + t_5)) - (sqrt(x) + sqrt(y));
      	} else {
      		tmp = (((fma(0.5, x, 1.0) - sqrt(x)) + (1.0 - sqrt(y))) + t_2) + t_3;
      	}
      	return tmp;
      }
      
      x, y, z, t = sort([x, y, z, t])
      function code(x, y, z, t)
      	t_1 = sqrt(Float64(1.0 + x))
      	t_2 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
      	t_3 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
      	t_4 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(sqrt(Float64(y + 1.0)) - sqrt(y))) + t_2) + t_3)
      	t_5 = Float64(0.5 * Float64(1.0 / sqrt(z)))
      	tmp = 0.0
      	if (t_4 <= 1.0001)
      		tmp = Float64(Float64(t_1 + fma(0.5, Float64(1.0 / sqrt(y)), t_5)) - sqrt(x));
      	elseif (t_4 <= 2.0001)
      		tmp = Float64(Float64(t_1 + Float64(sqrt(Float64(1.0 + y)) + t_5)) - Float64(sqrt(x) + sqrt(y)));
      	else
      		tmp = Float64(Float64(Float64(Float64(fma(0.5, x, 1.0) - sqrt(x)) + Float64(1.0 - sqrt(y))) + t_2) + 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[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(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] + t$95$2), $MachinePrecision] + t$95$3), $MachinePrecision]}, Block[{t$95$5 = N[(0.5 * N[(1.0 / N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$4, 1.0001], N[(N[(t$95$1 + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision] + t$95$5), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$4, 2.0001], N[(N[(t$95$1 + N[(N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision] + t$95$5), $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(N[(0.5 * x + 1.0), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(1.0 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$2), $MachinePrecision] + t$95$3), $MachinePrecision]]]]]]]]
      
      \begin{array}{l}
      [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
      \\
      \begin{array}{l}
      t_1 := \sqrt{1 + x}\\
      t_2 := \sqrt{z + 1} - \sqrt{z}\\
      t_3 := \sqrt{t + 1} - \sqrt{t}\\
      t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + t\_2\right) + t\_3\\
      t_5 := 0.5 \cdot \frac{1}{\sqrt{z}}\\
      \mathbf{if}\;t\_4 \leq 1.0001:\\
      \;\;\;\;\left(t\_1 + \mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, t\_5\right)\right) - \sqrt{x}\\
      
      \mathbf{elif}\;t\_4 \leq 2.0001:\\
      \;\;\;\;\left(t\_1 + \left(\sqrt{1 + y} + t\_5\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + \left(1 - \sqrt{y}\right)\right) + t\_2\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))) < 1.00009999999999999

        1. Initial program 77.8%

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

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

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

            \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
        4. Applied rewrites3.8%

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

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

            \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
        7. Applied rewrites3.8%

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

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

            \[\leadsto \left(\sqrt{1 + x} + \left(\frac{1}{2} \cdot \sqrt{\frac{1}{y}} + \frac{1}{2} \cdot \sqrt{\frac{1}{z}}\right)\right) - \sqrt{x} \]
        10. Applied rewrites81.3%

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

        if 1.00009999999999999 < (+.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))) < 2.00010000000000021

        1. Initial program 96.6%

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

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

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

            \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
        4. Applied rewrites14.9%

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

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

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right)\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
        7. Applied rewrites99.2%

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

        if 2.00010000000000021 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

        1. Initial program 98.5%

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

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

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

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

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

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

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

        Alternative 5: 93.0% accurate, 0.5× speedup?

        \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1} - \sqrt{z}\\ t_2 := \sqrt{x + 1} - \sqrt{x}\\ t_3 := \sqrt{t + 1} - \sqrt{t}\\ \mathbf{if}\;\left(\left(t\_2 + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + t\_1\right) + t\_3 \leq 0.9998:\\ \;\;\;\;\left(\left(t\_2 + \frac{1}{1 + \sqrt{y}}\right) + t\_1\right) + \left(\sqrt{t} - \sqrt{t}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(1 + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) - \sqrt{x}\right) + t\_1\right) + t\_3\\ \end{array} \end{array} \]
        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)) (sqrt z)))
                (t_2 (- (sqrt (+ x 1.0)) (sqrt x)))
                (t_3 (- (sqrt (+ t 1.0)) (sqrt t))))
           (if (<= (+ (+ (+ t_2 (- (sqrt (+ y 1.0)) (sqrt y))) t_1) t_3) 0.9998)
             (+ (+ (+ t_2 (/ 1.0 (+ 1.0 (sqrt y)))) t_1) (- (sqrt t) (sqrt t)))
             (+
              (+ (- (+ 1.0 (/ 1.0 (+ (sqrt y) (sqrt (+ 1.0 y))))) (sqrt x)) t_1)
              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)) - sqrt(z);
        	double t_2 = sqrt((x + 1.0)) - sqrt(x);
        	double t_3 = sqrt((t + 1.0)) - sqrt(t);
        	double tmp;
        	if ((((t_2 + (sqrt((y + 1.0)) - sqrt(y))) + t_1) + t_3) <= 0.9998) {
        		tmp = ((t_2 + (1.0 / (1.0 + sqrt(y)))) + t_1) + (sqrt(t) - sqrt(t));
        	} else {
        		tmp = (((1.0 + (1.0 / (sqrt(y) + sqrt((1.0 + y))))) - sqrt(x)) + t_1) + 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((z + 1.0d0)) - sqrt(z)
            t_2 = sqrt((x + 1.0d0)) - sqrt(x)
            t_3 = sqrt((t + 1.0d0)) - sqrt(t)
            if ((((t_2 + (sqrt((y + 1.0d0)) - sqrt(y))) + t_1) + t_3) <= 0.9998d0) then
                tmp = ((t_2 + (1.0d0 / (1.0d0 + sqrt(y)))) + t_1) + (sqrt(t) - sqrt(t))
            else
                tmp = (((1.0d0 + (1.0d0 / (sqrt(y) + sqrt((1.0d0 + y))))) - sqrt(x)) + t_1) + 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((z + 1.0)) - Math.sqrt(z);
        	double t_2 = Math.sqrt((x + 1.0)) - Math.sqrt(x);
        	double t_3 = Math.sqrt((t + 1.0)) - Math.sqrt(t);
        	double tmp;
        	if ((((t_2 + (Math.sqrt((y + 1.0)) - Math.sqrt(y))) + t_1) + t_3) <= 0.9998) {
        		tmp = ((t_2 + (1.0 / (1.0 + Math.sqrt(y)))) + t_1) + (Math.sqrt(t) - Math.sqrt(t));
        	} else {
        		tmp = (((1.0 + (1.0 / (Math.sqrt(y) + Math.sqrt((1.0 + y))))) - Math.sqrt(x)) + t_1) + t_3;
        	}
        	return tmp;
        }
        
        [x, y, z, t] = sort([x, y, z, t])
        def code(x, y, z, t):
        	t_1 = math.sqrt((z + 1.0)) - math.sqrt(z)
        	t_2 = math.sqrt((x + 1.0)) - math.sqrt(x)
        	t_3 = math.sqrt((t + 1.0)) - math.sqrt(t)
        	tmp = 0
        	if (((t_2 + (math.sqrt((y + 1.0)) - math.sqrt(y))) + t_1) + t_3) <= 0.9998:
        		tmp = ((t_2 + (1.0 / (1.0 + math.sqrt(y)))) + t_1) + (math.sqrt(t) - math.sqrt(t))
        	else:
        		tmp = (((1.0 + (1.0 / (math.sqrt(y) + math.sqrt((1.0 + y))))) - math.sqrt(x)) + t_1) + t_3
        	return tmp
        
        x, y, z, t = sort([x, y, z, t])
        function code(x, y, z, t)
        	t_1 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
        	t_2 = Float64(sqrt(Float64(x + 1.0)) - sqrt(x))
        	t_3 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
        	tmp = 0.0
        	if (Float64(Float64(Float64(t_2 + Float64(sqrt(Float64(y + 1.0)) - sqrt(y))) + t_1) + t_3) <= 0.9998)
        		tmp = Float64(Float64(Float64(t_2 + Float64(1.0 / Float64(1.0 + sqrt(y)))) + t_1) + Float64(sqrt(t) - sqrt(t)));
        	else
        		tmp = Float64(Float64(Float64(Float64(1.0 + Float64(1.0 / Float64(sqrt(y) + sqrt(Float64(1.0 + y))))) - sqrt(x)) + t_1) + 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((z + 1.0)) - sqrt(z);
        	t_2 = sqrt((x + 1.0)) - sqrt(x);
        	t_3 = sqrt((t + 1.0)) - sqrt(t);
        	tmp = 0.0;
        	if ((((t_2 + (sqrt((y + 1.0)) - sqrt(y))) + t_1) + t_3) <= 0.9998)
        		tmp = ((t_2 + (1.0 / (1.0 + sqrt(y)))) + t_1) + (sqrt(t) - sqrt(t));
        	else
        		tmp = (((1.0 + (1.0 / (sqrt(y) + sqrt((1.0 + y))))) - sqrt(x)) + t_1) + 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[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(t$95$2 + N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$3), $MachinePrecision], 0.9998], N[(N[(N[(t$95$2 + N[(1.0 / N[(1.0 + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision] + N[(N[Sqrt[t], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(1.0 + N[(1.0 / N[(N[Sqrt[y], $MachinePrecision] + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$1), $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} - \sqrt{z}\\
        t_2 := \sqrt{x + 1} - \sqrt{x}\\
        t_3 := \sqrt{t + 1} - \sqrt{t}\\
        \mathbf{if}\;\left(\left(t\_2 + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + t\_1\right) + t\_3 \leq 0.9998:\\
        \;\;\;\;\left(\left(t\_2 + \frac{1}{1 + \sqrt{y}}\right) + t\_1\right) + \left(\sqrt{t} - \sqrt{t}\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\left(\left(\left(1 + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) - \sqrt{x}\right) + t\_1\right) + t\_3\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 0.99980000000000002

          1. Initial program 20.2%

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

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

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

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

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

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

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

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          3. Applied rewrites20.3%

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

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

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

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

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

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

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

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{y}}, \frac{1}{2} \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            8. lift-sqrt.f6425.5

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{y}}, 0.5 \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          6. Applied rewrites25.5%

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

            \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left(\frac{-1}{8}, \frac{1}{\sqrt{y}}, \frac{1}{2} \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{\color{blue}{t}} - \sqrt{t}\right) \]
          8. Step-by-step derivation
            1. Applied rewrites25.5%

              \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{\mathsf{fma}\left(-0.125, \frac{1}{\sqrt{y}}, 0.5 \cdot \sqrt{y}\right)}{y}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{\color{blue}{t}} - \sqrt{t}\right) \]
            2. Taylor expanded in y around 0

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

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

                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{1 + \color{blue}{\sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t} - \sqrt{t}\right) \]
              3. lift-sqrt.f6423.9

                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \frac{1}{1 + \sqrt{y}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t} - \sqrt{t}\right) \]
            4. Applied rewrites23.9%

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

            if 0.99980000000000002 < (+.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 97.0%

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

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

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

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

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

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

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

                \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            3. Applied rewrites97.2%

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

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

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

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

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

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

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

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

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

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

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

          Alternative 6: 92.8% accurate, 0.5× speedup?

          \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1} - \sqrt{z}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ t_3 := \sqrt{y + 1} - \sqrt{y}\\ \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2 \leq 1.0001:\\ \;\;\;\;\left(\sqrt{1 + x} + \mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, 0.5 \cdot \frac{1}{\sqrt{z}}\right)\right) - \sqrt{x}\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\ \end{array} \end{array} \]
          NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
          (FPCore (x y z t)
           :precision binary64
           (let* ((t_1 (- (sqrt (+ z 1.0)) (sqrt z)))
                  (t_2 (- (sqrt (+ t 1.0)) (sqrt t)))
                  (t_3 (- (sqrt (+ y 1.0)) (sqrt y))))
             (if (<= (+ (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) t_3) t_1) t_2) 1.0001)
               (-
                (+ (sqrt (+ 1.0 x)) (fma 0.5 (/ 1.0 (sqrt y)) (* 0.5 (/ 1.0 (sqrt z)))))
                (sqrt x))
               (+ (+ (+ (- (fma 0.5 x 1.0) (sqrt x)) t_3) t_1) t_2))))
          assert(x < y && y < z && z < t);
          double code(double x, double y, double z, double t) {
          	double t_1 = sqrt((z + 1.0)) - sqrt(z);
          	double t_2 = sqrt((t + 1.0)) - sqrt(t);
          	double t_3 = sqrt((y + 1.0)) - sqrt(y);
          	double tmp;
          	if (((((sqrt((x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2) <= 1.0001) {
          		tmp = (sqrt((1.0 + x)) + fma(0.5, (1.0 / sqrt(y)), (0.5 * (1.0 / sqrt(z))))) - sqrt(x);
          	} else {
          		tmp = (((fma(0.5, x, 1.0) - sqrt(x)) + t_3) + t_1) + t_2;
          	}
          	return tmp;
          }
          
          x, y, z, t = sort([x, y, z, t])
          function code(x, y, z, t)
          	t_1 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
          	t_2 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
          	t_3 = Float64(sqrt(Float64(y + 1.0)) - sqrt(y))
          	tmp = 0.0
          	if (Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2) <= 1.0001)
          		tmp = Float64(Float64(sqrt(Float64(1.0 + x)) + fma(0.5, Float64(1.0 / sqrt(y)), Float64(0.5 * Float64(1.0 / sqrt(z))))) - sqrt(x));
          	else
          		tmp = Float64(Float64(Float64(Float64(fma(0.5, x, 1.0) - sqrt(x)) + t_3) + t_1) + t_2);
          	end
          	return tmp
          end
          
          NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
          code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision], 1.0001], N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(N[(0.5 * x + 1.0), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision]]]]]
          
          \begin{array}{l}
          [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
          \\
          \begin{array}{l}
          t_1 := \sqrt{z + 1} - \sqrt{z}\\
          t_2 := \sqrt{t + 1} - \sqrt{t}\\
          t_3 := \sqrt{y + 1} - \sqrt{y}\\
          \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2 \leq 1.0001:\\
          \;\;\;\;\left(\sqrt{1 + x} + \mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, 0.5 \cdot \frac{1}{\sqrt{z}}\right)\right) - \sqrt{x}\\
          
          \mathbf{else}:\\
          \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.00009999999999999

            1. Initial program 77.8%

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

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

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

                \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
            4. Applied rewrites3.8%

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

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

                \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
            7. Applied rewrites3.8%

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

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

                \[\leadsto \left(\sqrt{1 + x} + \left(\frac{1}{2} \cdot \sqrt{\frac{1}{y}} + \frac{1}{2} \cdot \sqrt{\frac{1}{z}}\right)\right) - \sqrt{x} \]
            10. Applied rewrites81.3%

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

            if 1.00009999999999999 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

            1. Initial program 97.5%

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

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

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

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

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

          Alternative 7: 92.8% accurate, 0.5× speedup?

          \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1} - \sqrt{z}\\ t_2 := \sqrt{t + 1} - \sqrt{t}\\ t_3 := \sqrt{y + 1} - \sqrt{y}\\ \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2 \leq 1.0001:\\ \;\;\;\;\left(\sqrt{1 + x} + \mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, 0.5 \cdot \frac{1}{\sqrt{z}}\right)\right) - \sqrt{x}\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\ \end{array} \end{array} \]
          NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
          (FPCore (x y z t)
           :precision binary64
           (let* ((t_1 (- (sqrt (+ z 1.0)) (sqrt z)))
                  (t_2 (- (sqrt (+ t 1.0)) (sqrt t)))
                  (t_3 (- (sqrt (+ y 1.0)) (sqrt y))))
             (if (<= (+ (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) t_3) t_1) t_2) 1.0001)
               (-
                (+ (sqrt (+ 1.0 x)) (fma 0.5 (/ 1.0 (sqrt y)) (* 0.5 (/ 1.0 (sqrt z)))))
                (sqrt x))
               (+ (+ (+ (- 1.0 (sqrt x)) t_3) t_1) t_2))))
          assert(x < y && y < z && z < t);
          double code(double x, double y, double z, double t) {
          	double t_1 = sqrt((z + 1.0)) - sqrt(z);
          	double t_2 = sqrt((t + 1.0)) - sqrt(t);
          	double t_3 = sqrt((y + 1.0)) - sqrt(y);
          	double tmp;
          	if (((((sqrt((x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2) <= 1.0001) {
          		tmp = (sqrt((1.0 + x)) + fma(0.5, (1.0 / sqrt(y)), (0.5 * (1.0 / sqrt(z))))) - sqrt(x);
          	} else {
          		tmp = (((1.0 - sqrt(x)) + t_3) + t_1) + t_2;
          	}
          	return tmp;
          }
          
          x, y, z, t = sort([x, y, z, t])
          function code(x, y, z, t)
          	t_1 = Float64(sqrt(Float64(z + 1.0)) - sqrt(z))
          	t_2 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
          	t_3 = Float64(sqrt(Float64(y + 1.0)) - sqrt(y))
          	tmp = 0.0
          	if (Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + t_3) + t_1) + t_2) <= 1.0001)
          		tmp = Float64(Float64(sqrt(Float64(1.0 + x)) + fma(0.5, Float64(1.0 / sqrt(y)), Float64(0.5 * Float64(1.0 / sqrt(z))))) - sqrt(x));
          	else
          		tmp = Float64(Float64(Float64(Float64(1.0 - sqrt(x)) + t_3) + t_1) + t_2);
          	end
          	return tmp
          end
          
          NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
          code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision], 1.0001], N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(1.0 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$3), $MachinePrecision] + t$95$1), $MachinePrecision] + t$95$2), $MachinePrecision]]]]]
          
          \begin{array}{l}
          [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
          \\
          \begin{array}{l}
          t_1 := \sqrt{z + 1} - \sqrt{z}\\
          t_2 := \sqrt{t + 1} - \sqrt{t}\\
          t_3 := \sqrt{y + 1} - \sqrt{y}\\
          \mathbf{if}\;\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2 \leq 1.0001:\\
          \;\;\;\;\left(\sqrt{1 + x} + \mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, 0.5 \cdot \frac{1}{\sqrt{z}}\right)\right) - \sqrt{x}\\
          
          \mathbf{else}:\\
          \;\;\;\;\left(\left(\left(1 - \sqrt{x}\right) + t\_3\right) + t\_1\right) + t\_2\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.00009999999999999

            1. Initial program 77.8%

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

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

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

                \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
            4. Applied rewrites3.8%

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

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

                \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
            7. Applied rewrites3.8%

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

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

                \[\leadsto \left(\sqrt{1 + x} + \left(\frac{1}{2} \cdot \sqrt{\frac{1}{y}} + \frac{1}{2} \cdot \sqrt{\frac{1}{z}}\right)\right) - \sqrt{x} \]
            10. Applied rewrites81.3%

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

            if 1.00009999999999999 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

            1. Initial program 97.5%

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

              \[\leadsto \left(\left(\left(\color{blue}{1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            3. Step-by-step derivation
              1. Applied rewrites97.4%

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

            Alternative 8: 92.3% accurate, 0.9× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{t + 1} - \sqrt{t}\\ \mathbf{if}\;\sqrt{y + 1} - \sqrt{y} \leq 0.999999999999:\\ \;\;\;\;\left(\left(\sqrt{1 + x} + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) - \sqrt{x}\right) + t\_1\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + \left(1 - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + t\_1\\ \end{array} \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t)
             :precision binary64
             (let* ((t_1 (- (sqrt (+ t 1.0)) (sqrt t))))
               (if (<= (- (sqrt (+ y 1.0)) (sqrt y)) 0.999999999999)
                 (+
                  (- (+ (sqrt (+ 1.0 x)) (/ 1.0 (+ (sqrt y) (sqrt (+ 1.0 y))))) (sqrt x))
                  t_1)
                 (+
                  (+
                   (+ (- (fma 0.5 x 1.0) (sqrt x)) (- 1.0 (sqrt y)))
                   (- (sqrt (+ z 1.0)) (sqrt z)))
                  t_1))))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	double t_1 = sqrt((t + 1.0)) - sqrt(t);
            	double tmp;
            	if ((sqrt((y + 1.0)) - sqrt(y)) <= 0.999999999999) {
            		tmp = ((sqrt((1.0 + x)) + (1.0 / (sqrt(y) + sqrt((1.0 + y))))) - sqrt(x)) + t_1;
            	} else {
            		tmp = (((fma(0.5, x, 1.0) - sqrt(x)) + (1.0 - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + t_1;
            	}
            	return tmp;
            }
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	t_1 = Float64(sqrt(Float64(t + 1.0)) - sqrt(t))
            	tmp = 0.0
            	if (Float64(sqrt(Float64(y + 1.0)) - sqrt(y)) <= 0.999999999999)
            		tmp = Float64(Float64(Float64(sqrt(Float64(1.0 + x)) + Float64(1.0 / Float64(sqrt(y) + sqrt(Float64(1.0 + y))))) - sqrt(x)) + t_1);
            	else
            		tmp = Float64(Float64(Float64(Float64(fma(0.5, x, 1.0) - sqrt(x)) + Float64(1.0 - sqrt(y))) + Float64(sqrt(Float64(z + 1.0)) - sqrt(z))) + t_1);
            	end
            	return tmp
            end
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision], 0.999999999999], N[(N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[(1.0 / N[(N[Sqrt[y], $MachinePrecision] + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision], N[(N[(N[(N[(N[(0.5 * x + 1.0), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(1.0 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$1), $MachinePrecision]]]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \begin{array}{l}
            t_1 := \sqrt{t + 1} - \sqrt{t}\\
            \mathbf{if}\;\sqrt{y + 1} - \sqrt{y} \leq 0.999999999999:\\
            \;\;\;\;\left(\left(\sqrt{1 + x} + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) - \sqrt{x}\right) + t\_1\\
            
            \mathbf{else}:\\
            \;\;\;\;\left(\left(\left(\mathsf{fma}\left(0.5, x, 1\right) - \sqrt{x}\right) + \left(1 - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + t\_1\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y)) < 0.999999999999000022

              1. Initial program 81.7%

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

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

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

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

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

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

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

                  \[\leadsto \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\frac{\sqrt{1 + y} \cdot \sqrt{1 + y} - \sqrt{y} \cdot \sqrt{y}}{\sqrt{1 + y} + \sqrt{y}}}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              3. Applied rewrites82.2%

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

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

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

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

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

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

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

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

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

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

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                10. lift-sqrt.f6483.0

                  \[\leadsto \left(\left(\sqrt{1 + x} + \frac{1}{\sqrt{y} + \sqrt{1 + y}}\right) - \sqrt{x}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              6. Applied rewrites83.0%

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

              if 0.999999999999000022 < (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))

              1. Initial program 97.8%

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

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

                  \[\leadsto \left(\left(\left(\left(\frac{1}{2} \cdot x + \color{blue}{1}\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
                2. lower-fma.f6497.8

                  \[\leadsto \left(\left(\left(\mathsf{fma}\left(0.5, \color{blue}{x}, 1\right) - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              4. Applied rewrites97.8%

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

                \[\leadsto \left(\left(\left(\mathsf{fma}\left(\frac{1}{2}, x, 1\right) - \sqrt{x}\right) + \left(\color{blue}{1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              6. Step-by-step derivation
                1. Applied rewrites97.8%

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

              Alternative 9: 88.0% accurate, 0.4× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{1 + x}\\ t_3 := \sqrt{z + 1}\\ t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_3 - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ t_5 := 0.5 \cdot \frac{1}{\sqrt{z}}\\ \mathbf{if}\;t\_4 \leq 1.0001:\\ \;\;\;\;\left(t\_2 + \mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, t\_5\right)\right) - \sqrt{x}\\ \mathbf{elif}\;t\_4 \leq 2.002:\\ \;\;\;\;\left(t\_2 + \left(\sqrt{1 + y} + t\_5\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(t\_2 + t\_1\right) + t\_3\right) - \sqrt{x}\right) - \sqrt{z}\\ \end{array} \end{array} \]
              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 (+ y 1.0)))
                      (t_2 (sqrt (+ 1.0 x)))
                      (t_3 (sqrt (+ z 1.0)))
                      (t_4
                       (+
                        (+
                         (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- t_1 (sqrt y)))
                         (- t_3 (sqrt z)))
                        (- (sqrt (+ t 1.0)) (sqrt t))))
                      (t_5 (* 0.5 (/ 1.0 (sqrt z)))))
                 (if (<= t_4 1.0001)
                   (- (+ t_2 (fma 0.5 (/ 1.0 (sqrt y)) t_5)) (sqrt x))
                   (if (<= t_4 2.002)
                     (- (+ t_2 (+ (sqrt (+ 1.0 y)) t_5)) (+ (sqrt x) (sqrt y)))
                     (- (- (+ (+ t_2 t_1) t_3) (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((y + 1.0));
              	double t_2 = sqrt((1.0 + x));
              	double t_3 = sqrt((z + 1.0));
              	double t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_1 - sqrt(y))) + (t_3 - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
              	double t_5 = 0.5 * (1.0 / sqrt(z));
              	double tmp;
              	if (t_4 <= 1.0001) {
              		tmp = (t_2 + fma(0.5, (1.0 / sqrt(y)), t_5)) - sqrt(x);
              	} else if (t_4 <= 2.002) {
              		tmp = (t_2 + (sqrt((1.0 + y)) + t_5)) - (sqrt(x) + sqrt(y));
              	} else {
              		tmp = (((t_2 + t_1) + t_3) - sqrt(x)) - sqrt(z);
              	}
              	return tmp;
              }
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	t_1 = sqrt(Float64(y + 1.0))
              	t_2 = sqrt(Float64(1.0 + x))
              	t_3 = sqrt(Float64(z + 1.0))
              	t_4 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(t_1 - sqrt(y))) + Float64(t_3 - sqrt(z))) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)))
              	t_5 = Float64(0.5 * Float64(1.0 / sqrt(z)))
              	tmp = 0.0
              	if (t_4 <= 1.0001)
              		tmp = Float64(Float64(t_2 + fma(0.5, Float64(1.0 / sqrt(y)), t_5)) - sqrt(x));
              	elseif (t_4 <= 2.002)
              		tmp = Float64(Float64(t_2 + Float64(sqrt(Float64(1.0 + y)) + t_5)) - Float64(sqrt(x) + sqrt(y)));
              	else
              		tmp = Float64(Float64(Float64(Float64(t_2 + t_1) + t_3) - sqrt(x)) - sqrt(z));
              	end
              	return tmp
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$4 = N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(t$95$1 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$3 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[(0.5 * N[(1.0 / N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$4, 1.0001], N[(N[(t$95$2 + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision] + t$95$5), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$4, 2.002], N[(N[(t$95$2 + N[(N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision] + t$95$5), $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(t$95$2 + t$95$1), $MachinePrecision] + t$95$3), $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{y + 1}\\
              t_2 := \sqrt{1 + x}\\
              t_3 := \sqrt{z + 1}\\
              t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_3 - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\
              t_5 := 0.5 \cdot \frac{1}{\sqrt{z}}\\
              \mathbf{if}\;t\_4 \leq 1.0001:\\
              \;\;\;\;\left(t\_2 + \mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, t\_5\right)\right) - \sqrt{x}\\
              
              \mathbf{elif}\;t\_4 \leq 2.002:\\
              \;\;\;\;\left(t\_2 + \left(\sqrt{1 + y} + t\_5\right)\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(\left(\left(t\_2 + t\_1\right) + t\_3\right) - \sqrt{x}\right) - \sqrt{z}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 3 regimes
              2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.00009999999999999

                1. Initial program 77.8%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites3.8%

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
                7. Applied rewrites3.8%

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \left(\frac{1}{2} \cdot \sqrt{\frac{1}{y}} + \frac{1}{2} \cdot \sqrt{\frac{1}{z}}\right)\right) - \sqrt{x} \]
                10. Applied rewrites81.3%

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

                if 1.00009999999999999 < (+.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))) < 2.0019999999999998

                1. Initial program 96.5%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \frac{1}{2} \cdot \frac{1}{\sqrt{z}}\right)\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                7. Applied rewrites98.8%

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

                if 2.0019999999999998 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t)))

                1. Initial program 98.6%

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

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

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

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

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

                  \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z} \]
                6. Step-by-step derivation
                  1. lift-sqrt.f6480.8

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z} \]
                7. Applied rewrites80.8%

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

              Alternative 10: 86.9% accurate, 0.4× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{1 + x}\\ t_3 := \sqrt{z + 1}\\ t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_3 - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{if}\;t\_4 \leq 1.0001:\\ \;\;\;\;\left(t\_2 + \mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, 0.5 \cdot \frac{1}{\sqrt{z}}\right)\right) - \sqrt{x}\\ \mathbf{elif}\;t\_4 \leq 2:\\ \;\;\;\;\left(t\_2 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(t\_2 + t\_1\right) + t\_3\right) - \sqrt{x}\right) - \sqrt{z}\\ \end{array} \end{array} \]
              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 (+ y 1.0)))
                      (t_2 (sqrt (+ 1.0 x)))
                      (t_3 (sqrt (+ z 1.0)))
                      (t_4
                       (+
                        (+
                         (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- t_1 (sqrt y)))
                         (- t_3 (sqrt z)))
                        (- (sqrt (+ t 1.0)) (sqrt t)))))
                 (if (<= t_4 1.0001)
                   (- (+ t_2 (fma 0.5 (/ 1.0 (sqrt y)) (* 0.5 (/ 1.0 (sqrt z))))) (sqrt x))
                   (if (<= t_4 2.0)
                     (- (+ t_2 (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                     (- (- (+ (+ t_2 t_1) t_3) (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((y + 1.0));
              	double t_2 = sqrt((1.0 + x));
              	double t_3 = sqrt((z + 1.0));
              	double t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_1 - sqrt(y))) + (t_3 - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
              	double tmp;
              	if (t_4 <= 1.0001) {
              		tmp = (t_2 + fma(0.5, (1.0 / sqrt(y)), (0.5 * (1.0 / sqrt(z))))) - sqrt(x);
              	} else if (t_4 <= 2.0) {
              		tmp = (t_2 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
              	} else {
              		tmp = (((t_2 + t_1) + t_3) - sqrt(x)) - sqrt(z);
              	}
              	return tmp;
              }
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	t_1 = sqrt(Float64(y + 1.0))
              	t_2 = sqrt(Float64(1.0 + x))
              	t_3 = sqrt(Float64(z + 1.0))
              	t_4 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(t_1 - sqrt(y))) + Float64(t_3 - sqrt(z))) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)))
              	tmp = 0.0
              	if (t_4 <= 1.0001)
              		tmp = Float64(Float64(t_2 + fma(0.5, Float64(1.0 / sqrt(y)), Float64(0.5 * Float64(1.0 / sqrt(z))))) - sqrt(x));
              	elseif (t_4 <= 2.0)
              		tmp = Float64(Float64(t_2 + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
              	else
              		tmp = Float64(Float64(Float64(Float64(t_2 + t_1) + t_3) - sqrt(x)) - sqrt(z));
              	end
              	return tmp
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$4 = N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(t$95$1 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$3 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$4, 1.0001], N[(N[(t$95$2 + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$4, 2.0], N[(N[(t$95$2 + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(t$95$2 + t$95$1), $MachinePrecision] + t$95$3), $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{y + 1}\\
              t_2 := \sqrt{1 + x}\\
              t_3 := \sqrt{z + 1}\\
              t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_3 - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\
              \mathbf{if}\;t\_4 \leq 1.0001:\\
              \;\;\;\;\left(t\_2 + \mathsf{fma}\left(0.5, \frac{1}{\sqrt{y}}, 0.5 \cdot \frac{1}{\sqrt{z}}\right)\right) - \sqrt{x}\\
              
              \mathbf{elif}\;t\_4 \leq 2:\\
              \;\;\;\;\left(t\_2 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(\left(\left(t\_2 + t\_1\right) + t\_3\right) - \sqrt{x}\right) - \sqrt{z}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 3 regimes
              2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.00009999999999999

                1. Initial program 77.8%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites3.8%

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
                7. Applied rewrites3.8%

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \left(\frac{1}{2} \cdot \sqrt{\frac{1}{y}} + \frac{1}{2} \cdot \sqrt{\frac{1}{z}}\right)\right) - \sqrt{x} \]
                10. Applied rewrites81.3%

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

                if 1.00009999999999999 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2

                1. Initial program 97.8%

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

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

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

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  9. lift-sqrt.f6497.5

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                7. Applied rewrites97.5%

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

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

                1. Initial program 97.2%

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

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

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

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

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

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

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z} \]
                7. Applied rewrites80.6%

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

              Alternative 11: 86.9% accurate, 0.4× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{1 + x}\\ t_3 := \sqrt{z + 1}\\ t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_3 - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ \mathbf{if}\;t\_4 \leq 1.0001:\\ \;\;\;\;\left(t\_2 + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\\ \mathbf{elif}\;t\_4 \leq 2:\\ \;\;\;\;\left(t\_2 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\left(t\_2 + t\_1\right) + t\_3\right) - \sqrt{x}\right) - \sqrt{z}\\ \end{array} \end{array} \]
              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 (+ y 1.0)))
                      (t_2 (sqrt (+ 1.0 x)))
                      (t_3 (sqrt (+ z 1.0)))
                      (t_4
                       (+
                        (+
                         (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- t_1 (sqrt y)))
                         (- t_3 (sqrt z)))
                        (- (sqrt (+ t 1.0)) (sqrt t)))))
                 (if (<= t_4 1.0001)
                   (- (+ t_2 (* 0.5 (/ 1.0 (sqrt y)))) (sqrt x))
                   (if (<= t_4 2.0)
                     (- (+ t_2 (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                     (- (- (+ (+ t_2 t_1) t_3) (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((y + 1.0));
              	double t_2 = sqrt((1.0 + x));
              	double t_3 = sqrt((z + 1.0));
              	double t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_1 - sqrt(y))) + (t_3 - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
              	double tmp;
              	if (t_4 <= 1.0001) {
              		tmp = (t_2 + (0.5 * (1.0 / sqrt(y)))) - sqrt(x);
              	} else if (t_4 <= 2.0) {
              		tmp = (t_2 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
              	} else {
              		tmp = (((t_2 + t_1) + t_3) - sqrt(x)) - sqrt(z);
              	}
              	return tmp;
              }
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(x, y, z, t)
              use fmin_fmax_functions
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  real(8) :: t_1
                  real(8) :: t_2
                  real(8) :: t_3
                  real(8) :: t_4
                  real(8) :: tmp
                  t_1 = sqrt((y + 1.0d0))
                  t_2 = sqrt((1.0d0 + x))
                  t_3 = sqrt((z + 1.0d0))
                  t_4 = (((sqrt((x + 1.0d0)) - sqrt(x)) + (t_1 - sqrt(y))) + (t_3 - sqrt(z))) + (sqrt((t + 1.0d0)) - sqrt(t))
                  if (t_4 <= 1.0001d0) then
                      tmp = (t_2 + (0.5d0 * (1.0d0 / sqrt(y)))) - sqrt(x)
                  else if (t_4 <= 2.0d0) then
                      tmp = (t_2 + sqrt((1.0d0 + y))) - (sqrt(x) + sqrt(y))
                  else
                      tmp = (((t_2 + t_1) + t_3) - 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((y + 1.0));
              	double t_2 = Math.sqrt((1.0 + x));
              	double t_3 = Math.sqrt((z + 1.0));
              	double t_4 = (((Math.sqrt((x + 1.0)) - Math.sqrt(x)) + (t_1 - Math.sqrt(y))) + (t_3 - Math.sqrt(z))) + (Math.sqrt((t + 1.0)) - Math.sqrt(t));
              	double tmp;
              	if (t_4 <= 1.0001) {
              		tmp = (t_2 + (0.5 * (1.0 / Math.sqrt(y)))) - Math.sqrt(x);
              	} else if (t_4 <= 2.0) {
              		tmp = (t_2 + Math.sqrt((1.0 + y))) - (Math.sqrt(x) + Math.sqrt(y));
              	} else {
              		tmp = (((t_2 + t_1) + t_3) - 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((y + 1.0))
              	t_2 = math.sqrt((1.0 + x))
              	t_3 = math.sqrt((z + 1.0))
              	t_4 = (((math.sqrt((x + 1.0)) - math.sqrt(x)) + (t_1 - math.sqrt(y))) + (t_3 - math.sqrt(z))) + (math.sqrt((t + 1.0)) - math.sqrt(t))
              	tmp = 0
              	if t_4 <= 1.0001:
              		tmp = (t_2 + (0.5 * (1.0 / math.sqrt(y)))) - math.sqrt(x)
              	elif t_4 <= 2.0:
              		tmp = (t_2 + math.sqrt((1.0 + y))) - (math.sqrt(x) + math.sqrt(y))
              	else:
              		tmp = (((t_2 + t_1) + t_3) - 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(y + 1.0))
              	t_2 = sqrt(Float64(1.0 + x))
              	t_3 = sqrt(Float64(z + 1.0))
              	t_4 = Float64(Float64(Float64(Float64(sqrt(Float64(x + 1.0)) - sqrt(x)) + Float64(t_1 - sqrt(y))) + Float64(t_3 - sqrt(z))) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)))
              	tmp = 0.0
              	if (t_4 <= 1.0001)
              		tmp = Float64(Float64(t_2 + Float64(0.5 * Float64(1.0 / sqrt(y)))) - sqrt(x));
              	elseif (t_4 <= 2.0)
              		tmp = Float64(Float64(t_2 + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
              	else
              		tmp = Float64(Float64(Float64(Float64(t_2 + t_1) + t_3) - 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((y + 1.0));
              	t_2 = sqrt((1.0 + x));
              	t_3 = sqrt((z + 1.0));
              	t_4 = (((sqrt((x + 1.0)) - sqrt(x)) + (t_1 - sqrt(y))) + (t_3 - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
              	tmp = 0.0;
              	if (t_4 <= 1.0001)
              		tmp = (t_2 + (0.5 * (1.0 / sqrt(y)))) - sqrt(x);
              	elseif (t_4 <= 2.0)
              		tmp = (t_2 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
              	else
              		tmp = (((t_2 + t_1) + t_3) - 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[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$4 = N[(N[(N[(N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(t$95$1 - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$3 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$4, 1.0001], N[(N[(t$95$2 + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$4, 2.0], N[(N[(t$95$2 + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(t$95$2 + t$95$1), $MachinePrecision] + t$95$3), $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{y + 1}\\
              t_2 := \sqrt{1 + x}\\
              t_3 := \sqrt{z + 1}\\
              t_4 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(t\_1 - \sqrt{y}\right)\right) + \left(t\_3 - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\
              \mathbf{if}\;t\_4 \leq 1.0001:\\
              \;\;\;\;\left(t\_2 + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\\
              
              \mathbf{elif}\;t\_4 \leq 2:\\
              \;\;\;\;\left(t\_2 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(\left(\left(t\_2 + t\_1\right) + t\_3\right) - \sqrt{x}\right) - \sqrt{z}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 3 regimes
              2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.00009999999999999

                1. Initial program 77.8%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites3.8%

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
                7. Applied rewrites3.8%

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

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

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

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

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

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

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

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

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

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

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

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

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

                if 1.00009999999999999 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2

                1. Initial program 97.8%

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

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

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

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  9. lift-sqrt.f6497.5

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                7. Applied rewrites97.5%

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

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

                1. Initial program 97.2%

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

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

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

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

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

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

                    \[\leadsto \left(\left(\left(\sqrt{1 + x} + \sqrt{y + 1}\right) + \sqrt{z + 1}\right) - \sqrt{x}\right) - \sqrt{z} \]
                7. Applied rewrites80.6%

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

              Alternative 12: 83.0% accurate, 0.4× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{1 + x}\\ t_2 := \left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\\ t_3 := t\_1 + \sqrt{1 + y}\\ \mathbf{if}\;t\_2 \leq 1.0001:\\ \;\;\;\;\left(t\_1 + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\\ \mathbf{elif}\;t\_2 \leq 2.5:\\ \;\;\;\;t\_3 - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\left(1 + t\_3\right) - \sqrt{x}\right) - \sqrt{y}\\ \end{array} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t)
               :precision binary64
               (let* ((t_1 (sqrt (+ 1.0 x)))
                      (t_2
                       (+
                        (+
                         (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y)))
                         (- (sqrt (+ z 1.0)) (sqrt z)))
                        (- (sqrt (+ t 1.0)) (sqrt t))))
                      (t_3 (+ t_1 (sqrt (+ 1.0 y)))))
                 (if (<= t_2 1.0001)
                   (- (+ t_1 (* 0.5 (/ 1.0 (sqrt y)))) (sqrt x))
                   (if (<= t_2 2.5)
                     (- t_3 (+ (sqrt x) (sqrt y)))
                     (- (- (+ 1.0 t_3) (sqrt x)) (sqrt y))))))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	double t_1 = sqrt((1.0 + x));
              	double t_2 = (((sqrt((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
              	double t_3 = t_1 + sqrt((1.0 + y));
              	double tmp;
              	if (t_2 <= 1.0001) {
              		tmp = (t_1 + (0.5 * (1.0 / sqrt(y)))) - sqrt(x);
              	} else if (t_2 <= 2.5) {
              		tmp = t_3 - (sqrt(x) + sqrt(y));
              	} else {
              		tmp = ((1.0 + t_3) - sqrt(x)) - sqrt(y);
              	}
              	return tmp;
              }
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(x, y, z, t)
              use fmin_fmax_functions
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  real(8) :: t_1
                  real(8) :: t_2
                  real(8) :: t_3
                  real(8) :: tmp
                  t_1 = sqrt((1.0d0 + x))
                  t_2 = (((sqrt((x + 1.0d0)) - sqrt(x)) + (sqrt((y + 1.0d0)) - sqrt(y))) + (sqrt((z + 1.0d0)) - sqrt(z))) + (sqrt((t + 1.0d0)) - sqrt(t))
                  t_3 = t_1 + sqrt((1.0d0 + y))
                  if (t_2 <= 1.0001d0) then
                      tmp = (t_1 + (0.5d0 * (1.0d0 / sqrt(y)))) - sqrt(x)
                  else if (t_2 <= 2.5d0) then
                      tmp = t_3 - (sqrt(x) + sqrt(y))
                  else
                      tmp = ((1.0d0 + t_3) - sqrt(x)) - sqrt(y)
                  end if
                  code = tmp
              end function
              
              assert x < y && y < z && z < t;
              public static double code(double x, double y, double z, double t) {
              	double t_1 = Math.sqrt((1.0 + x));
              	double t_2 = (((Math.sqrt((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));
              	double t_3 = t_1 + Math.sqrt((1.0 + y));
              	double tmp;
              	if (t_2 <= 1.0001) {
              		tmp = (t_1 + (0.5 * (1.0 / Math.sqrt(y)))) - Math.sqrt(x);
              	} else if (t_2 <= 2.5) {
              		tmp = t_3 - (Math.sqrt(x) + Math.sqrt(y));
              	} else {
              		tmp = ((1.0 + t_3) - Math.sqrt(x)) - Math.sqrt(y);
              	}
              	return tmp;
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	t_1 = math.sqrt((1.0 + x))
              	t_2 = (((math.sqrt((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))
              	t_3 = t_1 + math.sqrt((1.0 + y))
              	tmp = 0
              	if t_2 <= 1.0001:
              		tmp = (t_1 + (0.5 * (1.0 / math.sqrt(y)))) - math.sqrt(x)
              	elif t_2 <= 2.5:
              		tmp = t_3 - (math.sqrt(x) + math.sqrt(y))
              	else:
              		tmp = ((1.0 + t_3) - math.sqrt(x)) - math.sqrt(y)
              	return tmp
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	t_1 = sqrt(Float64(1.0 + x))
              	t_2 = Float64(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)))
              	t_3 = Float64(t_1 + sqrt(Float64(1.0 + y)))
              	tmp = 0.0
              	if (t_2 <= 1.0001)
              		tmp = Float64(Float64(t_1 + Float64(0.5 * Float64(1.0 / sqrt(y)))) - sqrt(x));
              	elseif (t_2 <= 2.5)
              		tmp = Float64(t_3 - Float64(sqrt(x) + sqrt(y)));
              	else
              		tmp = Float64(Float64(Float64(1.0 + t_3) - sqrt(x)) - sqrt(y));
              	end
              	return tmp
              end
              
              x, y, z, t = num2cell(sort([x, y, z, t])){:}
              function tmp_2 = code(x, y, z, t)
              	t_1 = sqrt((1.0 + x));
              	t_2 = (((sqrt((x + 1.0)) - sqrt(x)) + (sqrt((y + 1.0)) - sqrt(y))) + (sqrt((z + 1.0)) - sqrt(z))) + (sqrt((t + 1.0)) - sqrt(t));
              	t_3 = t_1 + sqrt((1.0 + y));
              	tmp = 0.0;
              	if (t_2 <= 1.0001)
              		tmp = (t_1 + (0.5 * (1.0 / sqrt(y)))) - sqrt(x);
              	elseif (t_2 <= 2.5)
              		tmp = t_3 - (sqrt(x) + sqrt(y));
              	else
              		tmp = ((1.0 + t_3) - sqrt(x)) - sqrt(y);
              	end
              	tmp_2 = tmp;
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[(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]}, Block[{t$95$3 = N[(t$95$1 + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$2, 1.0001], N[(N[(t$95$1 + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$2, 2.5], N[(t$95$3 - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[(1.0 + t$95$3), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]]]]]]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \begin{array}{l}
              t_1 := \sqrt{1 + x}\\
              t_2 := \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)\\
              t_3 := t\_1 + \sqrt{1 + y}\\
              \mathbf{if}\;t\_2 \leq 1.0001:\\
              \;\;\;\;\left(t\_1 + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\\
              
              \mathbf{elif}\;t\_2 \leq 2.5:\\
              \;\;\;\;t\_3 - \left(\sqrt{x} + \sqrt{y}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(\left(1 + t\_3\right) - \sqrt{x}\right) - \sqrt{y}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 3 regimes
              2. if (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 1.00009999999999999

                1. Initial program 77.8%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites3.8%

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
                7. Applied rewrites3.8%

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

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

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

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

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

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

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

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

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

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

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

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

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

                if 1.00009999999999999 < (+.f64 (+.f64 (+.f64 (-.f64 (sqrt.f64 (+.f64 x #s(literal 1 binary64))) (sqrt.f64 x)) (-.f64 (sqrt.f64 (+.f64 y #s(literal 1 binary64))) (sqrt.f64 y))) (-.f64 (sqrt.f64 (+.f64 z #s(literal 1 binary64))) (sqrt.f64 z))) (-.f64 (sqrt.f64 (+.f64 t #s(literal 1 binary64))) (sqrt.f64 t))) < 2.5

                1. Initial program 96.5%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites17.9%

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

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

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

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

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

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

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

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                  9. lift-sqrt.f6492.6

                    \[\leadsto \left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right) \]
                7. Applied rewrites92.6%

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

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

                1. Initial program 98.7%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites81.3%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

              Alternative 13: 66.5% accurate, 1.8× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{1 + x}\\ \mathbf{if}\;y \leq 66000000:\\ \;\;\;\;\left(t\_1 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(t\_1 + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\\ \end{array} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t)
               :precision binary64
               (let* ((t_1 (sqrt (+ 1.0 x))))
                 (if (<= y 66000000.0)
                   (- (+ t_1 (sqrt (+ 1.0 y))) (+ (sqrt x) (sqrt y)))
                   (- (+ t_1 (* 0.5 (/ 1.0 (sqrt y)))) (sqrt x)))))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	double t_1 = sqrt((1.0 + x));
              	double tmp;
              	if (y <= 66000000.0) {
              		tmp = (t_1 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
              	} else {
              		tmp = (t_1 + (0.5 * (1.0 / sqrt(y)))) - sqrt(x);
              	}
              	return tmp;
              }
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(x, y, z, t)
              use fmin_fmax_functions
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  real(8) :: t_1
                  real(8) :: tmp
                  t_1 = sqrt((1.0d0 + x))
                  if (y <= 66000000.0d0) then
                      tmp = (t_1 + sqrt((1.0d0 + y))) - (sqrt(x) + sqrt(y))
                  else
                      tmp = (t_1 + (0.5d0 * (1.0d0 / sqrt(y)))) - sqrt(x)
                  end if
                  code = tmp
              end function
              
              assert x < y && y < z && z < t;
              public static double code(double x, double y, double z, double t) {
              	double t_1 = Math.sqrt((1.0 + x));
              	double tmp;
              	if (y <= 66000000.0) {
              		tmp = (t_1 + Math.sqrt((1.0 + y))) - (Math.sqrt(x) + Math.sqrt(y));
              	} else {
              		tmp = (t_1 + (0.5 * (1.0 / Math.sqrt(y)))) - Math.sqrt(x);
              	}
              	return tmp;
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	t_1 = math.sqrt((1.0 + x))
              	tmp = 0
              	if y <= 66000000.0:
              		tmp = (t_1 + math.sqrt((1.0 + y))) - (math.sqrt(x) + math.sqrt(y))
              	else:
              		tmp = (t_1 + (0.5 * (1.0 / math.sqrt(y)))) - math.sqrt(x)
              	return tmp
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	t_1 = sqrt(Float64(1.0 + x))
              	tmp = 0.0
              	if (y <= 66000000.0)
              		tmp = Float64(Float64(t_1 + sqrt(Float64(1.0 + y))) - Float64(sqrt(x) + sqrt(y)));
              	else
              		tmp = Float64(Float64(t_1 + Float64(0.5 * Float64(1.0 / sqrt(y)))) - sqrt(x));
              	end
              	return tmp
              end
              
              x, y, z, t = num2cell(sort([x, y, z, t])){:}
              function tmp_2 = code(x, y, z, t)
              	t_1 = sqrt((1.0 + x));
              	tmp = 0.0;
              	if (y <= 66000000.0)
              		tmp = (t_1 + sqrt((1.0 + y))) - (sqrt(x) + sqrt(y));
              	else
              		tmp = (t_1 + (0.5 * (1.0 / sqrt(y)))) - sqrt(x);
              	end
              	tmp_2 = tmp;
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[y, 66000000.0], N[(N[(t$95$1 + N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(t$95$1 + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]]]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \begin{array}{l}
              t_1 := \sqrt{1 + x}\\
              \mathbf{if}\;y \leq 66000000:\\
              \;\;\;\;\left(t\_1 + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(t\_1 + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if y < 6.6e7

                1. Initial program 97.4%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites45.7%

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

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

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

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

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

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

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

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

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

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

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

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

                if 6.6e7 < y

                1. Initial program 77.8%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites3.8%

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
                7. Applied rewrites3.7%

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

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

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

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

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

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

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

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

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

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

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

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

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

              Alternative 14: 33.8% accurate, 1.8× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} \mathbf{if}\;y \leq 3.8 \cdot 10^{-44}:\\ \;\;\;\;\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y}\\ \mathbf{else}:\\ \;\;\;\;\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\\ \end{array} \end{array} \]
              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 3.8e-44)
                 (- (+ (sqrt (+ 1.0 y)) (sqrt (+ 1.0 z))) (sqrt y))
                 (- (+ (sqrt (+ 1.0 x)) (* 0.5 (/ 1.0 (sqrt y)))) (sqrt x))))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	double tmp;
              	if (y <= 3.8e-44) {
              		tmp = (sqrt((1.0 + y)) + sqrt((1.0 + z))) - sqrt(y);
              	} else {
              		tmp = (sqrt((1.0 + x)) + (0.5 * (1.0 / sqrt(y)))) - sqrt(x);
              	}
              	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 <= 3.8d-44) then
                      tmp = (sqrt((1.0d0 + y)) + sqrt((1.0d0 + z))) - sqrt(y)
                  else
                      tmp = (sqrt((1.0d0 + x)) + (0.5d0 * (1.0d0 / sqrt(y)))) - sqrt(x)
                  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 <= 3.8e-44) {
              		tmp = (Math.sqrt((1.0 + y)) + Math.sqrt((1.0 + z))) - Math.sqrt(y);
              	} else {
              		tmp = (Math.sqrt((1.0 + x)) + (0.5 * (1.0 / Math.sqrt(y)))) - Math.sqrt(x);
              	}
              	return tmp;
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	tmp = 0
              	if y <= 3.8e-44:
              		tmp = (math.sqrt((1.0 + y)) + math.sqrt((1.0 + z))) - math.sqrt(y)
              	else:
              		tmp = (math.sqrt((1.0 + x)) + (0.5 * (1.0 / math.sqrt(y)))) - math.sqrt(x)
              	return tmp
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	tmp = 0.0
              	if (y <= 3.8e-44)
              		tmp = Float64(Float64(sqrt(Float64(1.0 + y)) + sqrt(Float64(1.0 + z))) - sqrt(y));
              	else
              		tmp = Float64(Float64(sqrt(Float64(1.0 + x)) + Float64(0.5 * Float64(1.0 / sqrt(y)))) - sqrt(x));
              	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 <= 3.8e-44)
              		tmp = (sqrt((1.0 + y)) + sqrt((1.0 + z))) - sqrt(y);
              	else
              		tmp = (sqrt((1.0 + x)) + (0.5 * (1.0 / sqrt(y)))) - sqrt(x);
              	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, 3.8e-44], N[(N[(N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision] + N[Sqrt[N[(1.0 + z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision], N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \begin{array}{l}
              \mathbf{if}\;y \leq 3.8 \cdot 10^{-44}:\\
              \;\;\;\;\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y}\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if y < 3.8000000000000001e-44

                1. Initial program 97.9%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites50.8%

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

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

                    \[\leadsto \sqrt{y} - \left(\sqrt{z} + \sqrt{y}\right) \]
                7. Applied rewrites1.6%

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

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

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

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

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

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

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

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

                    \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \]
                  5. lift-+.f6414.3

                    \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \]
                13. Applied rewrites14.3%

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

                if 3.8000000000000001e-44 < y

                1. Initial program 83.7%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites10.6%

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
                7. Applied rewrites4.8%

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \frac{1}{2} \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x} \]
                  10. lift-sqrt.f6460.3

                    \[\leadsto \left(\sqrt{1 + x} + 0.5 \cdot \frac{1}{\sqrt{y}}\right) - \sqrt{x} \]
                10. Applied rewrites60.3%

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

              Alternative 15: 12.4% accurate, 1.9× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} \mathbf{if}\;z \leq 3.15 \cdot 10^{+32}:\\ \;\;\;\;\left(\sqrt{1 + x} + \sqrt{z}\right) - \left(\sqrt{x} + \sqrt{z}\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \frac{1}{\sqrt{y}}\\ \end{array} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t)
               :precision binary64
               (if (<= z 3.15e+32)
                 (- (+ (sqrt (+ 1.0 x)) (sqrt z)) (+ (sqrt x) (sqrt z)))
                 (* 0.5 (/ 1.0 (sqrt y)))))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	double tmp;
              	if (z <= 3.15e+32) {
              		tmp = (sqrt((1.0 + x)) + sqrt(z)) - (sqrt(x) + sqrt(z));
              	} else {
              		tmp = 0.5 * (1.0 / 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) :: tmp
                  if (z <= 3.15d+32) then
                      tmp = (sqrt((1.0d0 + x)) + sqrt(z)) - (sqrt(x) + sqrt(z))
                  else
                      tmp = 0.5d0 * (1.0d0 / 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 tmp;
              	if (z <= 3.15e+32) {
              		tmp = (Math.sqrt((1.0 + x)) + Math.sqrt(z)) - (Math.sqrt(x) + Math.sqrt(z));
              	} else {
              		tmp = 0.5 * (1.0 / Math.sqrt(y));
              	}
              	return tmp;
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	tmp = 0
              	if z <= 3.15e+32:
              		tmp = (math.sqrt((1.0 + x)) + math.sqrt(z)) - (math.sqrt(x) + math.sqrt(z))
              	else:
              		tmp = 0.5 * (1.0 / math.sqrt(y))
              	return tmp
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	tmp = 0.0
              	if (z <= 3.15e+32)
              		tmp = Float64(Float64(sqrt(Float64(1.0 + x)) + sqrt(z)) - Float64(sqrt(x) + sqrt(z)));
              	else
              		tmp = Float64(0.5 * Float64(1.0 / sqrt(y)));
              	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 (z <= 3.15e+32)
              		tmp = (sqrt((1.0 + x)) + sqrt(z)) - (sqrt(x) + sqrt(z));
              	else
              		tmp = 0.5 * (1.0 / 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_] := If[LessEqual[z, 3.15e+32], N[(N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] + N[Sqrt[z], $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \begin{array}{l}
              \mathbf{if}\;z \leq 3.15 \cdot 10^{+32}:\\
              \;\;\;\;\left(\sqrt{1 + x} + \sqrt{z}\right) - \left(\sqrt{x} + \sqrt{z}\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;0.5 \cdot \frac{1}{\sqrt{y}}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if z < 3.1500000000000001e32

                1. Initial program 95.5%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites80.8%

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
                7. Applied rewrites7.6%

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

                  \[\leadsto \left(\sqrt{1 + x} + \sqrt{z}\right) - \left(\sqrt{x} + \sqrt{z}\right) \]
                9. Step-by-step derivation
                  1. lift-sqrt.f6418.4

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

                  \[\leadsto \left(\sqrt{1 + x} + \sqrt{z}\right) - \left(\sqrt{x} + \sqrt{z}\right) \]

                if 3.1500000000000001e32 < z

                1. Initial program 89.5%

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

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

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

                    \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
                4. Applied rewrites3.2%

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

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

                    \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
                7. Applied rewrites4.2%

                  \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \color{blue}{\left(\sqrt{x} + \sqrt{z}\right)} \]
                8. Taylor expanded in y around 0

                  \[\leadsto \frac{1}{2} \cdot \sqrt{\frac{1}{y}} \]
                9. Step-by-step derivation
                  1. lower-*.f64N/A

                    \[\leadsto \frac{1}{2} \cdot \sqrt{\frac{1}{y}} \]
                  2. sqrt-divN/A

                    \[\leadsto \frac{1}{2} \cdot \frac{\sqrt{1}}{\sqrt{y}} \]
                  3. metadata-evalN/A

                    \[\leadsto \frac{1}{2} \cdot \frac{1}{\sqrt{y}} \]
                  4. lift-sqrt.f64N/A

                    \[\leadsto \frac{1}{2} \cdot \frac{1}{\sqrt{y}} \]
                  5. lift-/.f648.5

                    \[\leadsto 0.5 \cdot \frac{1}{\sqrt{y}} \]
                10. Applied rewrites8.5%

                  \[\leadsto 0.5 \cdot \frac{1}{\color{blue}{\sqrt{y}}} \]
              3. Recombined 2 regimes into one program.
              4. Add Preprocessing

              Alternative 16: 11.3% accurate, 2.7× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t)
               :precision binary64
               (- (+ (sqrt (+ 1.0 y)) (sqrt (+ 1.0 z))) (sqrt y)))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	return (sqrt((1.0 + y)) + sqrt((1.0 + z))) - sqrt(y);
              }
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(x, y, z, t)
              use fmin_fmax_functions
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  code = (sqrt((1.0d0 + y)) + sqrt((1.0d0 + z))) - sqrt(y)
              end function
              
              assert x < y && y < z && z < t;
              public static double code(double x, double y, double z, double t) {
              	return (Math.sqrt((1.0 + y)) + Math.sqrt((1.0 + z))) - Math.sqrt(y);
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	return (math.sqrt((1.0 + y)) + math.sqrt((1.0 + z))) - math.sqrt(y)
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	return Float64(Float64(sqrt(Float64(1.0 + y)) + sqrt(Float64(1.0 + z))) - sqrt(y))
              end
              
              x, y, z, t = num2cell(sort([x, y, z, t])){:}
              function tmp = code(x, y, z, t)
              	tmp = (sqrt((1.0 + y)) + sqrt((1.0 + z))) - sqrt(y);
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := N[(N[(N[Sqrt[N[(1.0 + y), $MachinePrecision]], $MachinePrecision] + N[Sqrt[N[(1.0 + z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y}
              \end{array}
              
              Derivation
              1. Initial program 91.9%

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

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

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

                  \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
              4. Applied rewrites33.8%

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

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

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

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

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

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

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

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

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

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

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

                  \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \]
                5. lift-+.f6411.3

                  \[\leadsto \left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{y} \]
              13. Applied rewrites11.3%

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

              Alternative 17: 7.9% accurate, 4.2× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ 0.5 \cdot \frac{1}{\sqrt{y}} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t) :precision binary64 (* 0.5 (/ 1.0 (sqrt y))))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	return 0.5 * (1.0 / 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 = 0.5d0 * (1.0d0 / sqrt(y))
              end function
              
              assert x < y && y < z && z < t;
              public static double code(double x, double y, double z, double t) {
              	return 0.5 * (1.0 / Math.sqrt(y));
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	return 0.5 * (1.0 / math.sqrt(y))
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	return Float64(0.5 * Float64(1.0 / sqrt(y)))
              end
              
              x, y, z, t = num2cell(sort([x, y, z, t])){:}
              function tmp = code(x, y, z, t)
              	tmp = 0.5 * (1.0 / 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[(0.5 * N[(1.0 / N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              0.5 \cdot \frac{1}{\sqrt{y}}
              \end{array}
              
              Derivation
              1. Initial program 91.9%

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

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

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

                  \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
              4. Applied rewrites33.8%

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

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

                  \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + \frac{1}{2} \cdot \sqrt{\frac{1}{y}}\right)\right) - \left(\sqrt{x} + \color{blue}{\sqrt{z}}\right) \]
              7. Applied rewrites5.5%

                \[\leadsto \left(\sqrt{1 + x} + \left(\sqrt{1 + z} + 0.5 \cdot \frac{1}{\sqrt{y}}\right)\right) - \color{blue}{\left(\sqrt{x} + \sqrt{z}\right)} \]
              8. Taylor expanded in y around 0

                \[\leadsto \frac{1}{2} \cdot \sqrt{\frac{1}{y}} \]
              9. Step-by-step derivation
                1. lower-*.f64N/A

                  \[\leadsto \frac{1}{2} \cdot \sqrt{\frac{1}{y}} \]
                2. sqrt-divN/A

                  \[\leadsto \frac{1}{2} \cdot \frac{\sqrt{1}}{\sqrt{y}} \]
                3. metadata-evalN/A

                  \[\leadsto \frac{1}{2} \cdot \frac{1}{\sqrt{y}} \]
                4. lift-sqrt.f64N/A

                  \[\leadsto \frac{1}{2} \cdot \frac{1}{\sqrt{y}} \]
                5. lift-/.f647.9

                  \[\leadsto 0.5 \cdot \frac{1}{\sqrt{y}} \]
              10. Applied rewrites7.9%

                \[\leadsto 0.5 \cdot \frac{1}{\color{blue}{\sqrt{y}}} \]
              11. Add Preprocessing

              Alternative 18: 7.6% accurate, 4.8× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \sqrt{z} - \sqrt{y} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t) :precision binary64 (- (sqrt z) (sqrt y)))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	return sqrt(z) - sqrt(y);
              }
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(x, y, z, t)
              use fmin_fmax_functions
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  code = sqrt(z) - sqrt(y)
              end function
              
              assert x < y && y < z && z < t;
              public static double code(double x, double y, double z, double t) {
              	return Math.sqrt(z) - Math.sqrt(y);
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	return math.sqrt(z) - math.sqrt(y)
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	return Float64(sqrt(z) - sqrt(y))
              end
              
              x, y, z, t = num2cell(sort([x, y, z, t])){:}
              function tmp = code(x, y, z, t)
              	tmp = sqrt(z) - sqrt(y);
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := N[(N[Sqrt[z], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \sqrt{z} - \sqrt{y}
              \end{array}
              
              Derivation
              1. Initial program 91.9%

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

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

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

                  \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
              4. Applied rewrites33.8%

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

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

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

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

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

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

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

                \[\leadsto \sqrt{z} - \sqrt{\color{blue}{y}} \]
              12. Step-by-step derivation
                1. lift-sqrt.f647.6

                  \[\leadsto \sqrt{z} - \sqrt{y} \]
              13. Applied rewrites7.6%

                \[\leadsto \sqrt{z} - \sqrt{\color{blue}{y}} \]
              14. Add Preprocessing

              Alternative 19: 3.1% accurate, 4.8× speedup?

              \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \sqrt{y} - \sqrt{y} \end{array} \]
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              (FPCore (x y z t) :precision binary64 (- (sqrt y) (sqrt y)))
              assert(x < y && y < z && z < t);
              double code(double x, double y, double z, double t) {
              	return sqrt(y) - sqrt(y);
              }
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(x, y, z, t)
              use fmin_fmax_functions
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  code = sqrt(y) - sqrt(y)
              end function
              
              assert x < y && y < z && z < t;
              public static double code(double x, double y, double z, double t) {
              	return Math.sqrt(y) - Math.sqrt(y);
              }
              
              [x, y, z, t] = sort([x, y, z, t])
              def code(x, y, z, t):
              	return math.sqrt(y) - math.sqrt(y)
              
              x, y, z, t = sort([x, y, z, t])
              function code(x, y, z, t)
              	return Float64(sqrt(y) - sqrt(y))
              end
              
              x, y, z, t = num2cell(sort([x, y, z, t])){:}
              function tmp = code(x, y, z, t)
              	tmp = sqrt(y) - sqrt(y);
              end
              
              NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
              code[x_, y_, z_, t_] := N[(N[Sqrt[y], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
              \\
              \sqrt{y} - \sqrt{y}
              \end{array}
              
              Derivation
              1. Initial program 91.9%

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

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

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

                  \[\leadsto \left(\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \sqrt{x}\right) - \color{blue}{\left(\sqrt{y} + \sqrt{z}\right)} \]
              4. Applied rewrites33.8%

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

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

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

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

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

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

                \[\leadsto \sqrt{y} - \sqrt{y} \]
              11. Add Preprocessing

              Reproduce

              ?
              herbie shell --seed 2025101 
              (FPCore (x y z t)
                :name "Main:z from "
                :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))))