Main:z from

Percentage Accurate: 92.1% → 97.8%
Time: 48.4s
Alternatives: 18
Speedup: 1.3×

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

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

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 18 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: 92.1% 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));
}
real(8) function code(x, y, z, t)
    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: 97.8% accurate, 0.3× speedup?

\[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\\ t_2 := \sqrt{y + 1}\\ t_3 := \sqrt{z + 1}\\ t_4 := t_3 - \sqrt{z}\\ t_5 := \sqrt{x + 1}\\ t_6 := \sqrt{x} + t_5\\ \mathbf{if}\;y \leq 6.5 \cdot 10^{+15}:\\ \;\;\;\;t_5 - \left(\sqrt{x} + \left(t_1 + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - t_3} - t_2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(1, t_2 + \left(t_4 + t_1\right), t_6 \cdot \left({\left(t_2 + t_4\right)}^{2} - {t_1}^{2}\right)\right)}{t_6 \cdot \left(t_2 + \left(\left(\sqrt{y} + -1\right) - \left(\sqrt{z} - t_3\right)\right)\right)}\\ \end{array} \end{array} \]
NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
(FPCore (x y z t)
 :precision binary64
 (let* ((t_1 (+ (sqrt y) (- (sqrt t) (sqrt (+ t 1.0)))))
        (t_2 (sqrt (+ y 1.0)))
        (t_3 (sqrt (+ z 1.0)))
        (t_4 (- t_3 (sqrt z)))
        (t_5 (sqrt (+ x 1.0)))
        (t_6 (+ (sqrt x) t_5)))
   (if (<= y 6.5e+15)
     (-
      t_5
      (+ (sqrt x) (+ t_1 (- (/ (+ (- z z) 1.0) (- (- (sqrt z)) t_3)) t_2))))
     (/
      (fma
       1.0
       (+ t_2 (+ t_4 t_1))
       (* t_6 (- (pow (+ t_2 t_4) 2.0) (pow t_1 2.0))))
      (* t_6 (+ t_2 (- (+ (sqrt y) -1.0) (- (sqrt z) t_3))))))))
assert(x < y && y < z && z < t);
double code(double x, double y, double z, double t) {
	double t_1 = sqrt(y) + (sqrt(t) - sqrt((t + 1.0)));
	double t_2 = sqrt((y + 1.0));
	double t_3 = sqrt((z + 1.0));
	double t_4 = t_3 - sqrt(z);
	double t_5 = sqrt((x + 1.0));
	double t_6 = sqrt(x) + t_5;
	double tmp;
	if (y <= 6.5e+15) {
		tmp = t_5 - (sqrt(x) + (t_1 + ((((z - z) + 1.0) / (-sqrt(z) - t_3)) - t_2)));
	} else {
		tmp = fma(1.0, (t_2 + (t_4 + t_1)), (t_6 * (pow((t_2 + t_4), 2.0) - pow(t_1, 2.0)))) / (t_6 * (t_2 + ((sqrt(y) + -1.0) - (sqrt(z) - t_3))));
	}
	return tmp;
}
x, y, z, t = sort([x, y, z, t])
function code(x, y, z, t)
	t_1 = Float64(sqrt(y) + Float64(sqrt(t) - sqrt(Float64(t + 1.0))))
	t_2 = sqrt(Float64(y + 1.0))
	t_3 = sqrt(Float64(z + 1.0))
	t_4 = Float64(t_3 - sqrt(z))
	t_5 = sqrt(Float64(x + 1.0))
	t_6 = Float64(sqrt(x) + t_5)
	tmp = 0.0
	if (y <= 6.5e+15)
		tmp = Float64(t_5 - Float64(sqrt(x) + Float64(t_1 + Float64(Float64(Float64(Float64(z - z) + 1.0) / Float64(Float64(-sqrt(z)) - t_3)) - t_2))));
	else
		tmp = Float64(fma(1.0, Float64(t_2 + Float64(t_4 + t_1)), Float64(t_6 * Float64((Float64(t_2 + t_4) ^ 2.0) - (t_1 ^ 2.0)))) / Float64(t_6 * Float64(t_2 + Float64(Float64(sqrt(y) + -1.0) - Float64(sqrt(z) - t_3)))));
	end
	return tmp
end
NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[Sqrt[y], $MachinePrecision] + N[(N[Sqrt[t], $MachinePrecision] - N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$4 = N[(t$95$3 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$6 = N[(N[Sqrt[x], $MachinePrecision] + t$95$5), $MachinePrecision]}, If[LessEqual[y, 6.5e+15], N[(t$95$5 - N[(N[Sqrt[x], $MachinePrecision] + N[(t$95$1 + N[(N[(N[(N[(z - z), $MachinePrecision] + 1.0), $MachinePrecision] / N[((-N[Sqrt[z], $MachinePrecision]) - t$95$3), $MachinePrecision]), $MachinePrecision] - t$95$2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 * N[(t$95$2 + N[(t$95$4 + t$95$1), $MachinePrecision]), $MachinePrecision] + N[(t$95$6 * N[(N[Power[N[(t$95$2 + t$95$4), $MachinePrecision], 2.0], $MachinePrecision] - N[Power[t$95$1, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(t$95$6 * N[(t$95$2 + N[(N[(N[Sqrt[y], $MachinePrecision] + -1.0), $MachinePrecision] - N[(N[Sqrt[z], $MachinePrecision] - t$95$3), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]]
\begin{array}{l}
[x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
\\
\begin{array}{l}
t_1 := \sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\\
t_2 := \sqrt{y + 1}\\
t_3 := \sqrt{z + 1}\\
t_4 := t_3 - \sqrt{z}\\
t_5 := \sqrt{x + 1}\\
t_6 := \sqrt{x} + t_5\\
\mathbf{if}\;y \leq 6.5 \cdot 10^{+15}:\\
\;\;\;\;t_5 - \left(\sqrt{x} + \left(t_1 + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - t_3} - t_2\right)\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{\mathsf{fma}\left(1, t_2 + \left(t_4 + t_1\right), t_6 \cdot \left({\left(t_2 + t_4\right)}^{2} - {t_1}^{2}\right)\right)}{t_6 \cdot \left(t_2 + \left(\left(\sqrt{y} + -1\right) - \left(\sqrt{z} - t_3\right)\right)\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < 6.5e15

    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. Step-by-step derivation
      1. associate-+l+96.5%

        \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
      2. associate-+l+96.5%

        \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
      3. +-commutative96.5%

        \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
      4. associate-+l+96.5%

        \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
      5. +-commutative96.5%

        \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
      6. associate-+l-49.5%

        \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
    3. Simplified49.5%

      \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
    4. Step-by-step derivation
      1. flip--49.5%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{1 + z} + \sqrt{z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      2. frac-2neg49.5%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      3. add-sqr-sqrt41.7%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\color{blue}{\left(1 + z\right)} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      4. add-sqr-sqrt49.7%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\left(1 + z\right) - \color{blue}{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
    5. Applied egg-rr49.7%

      \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
    6. Step-by-step derivation
      1. neg-sub049.7%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{0 - \left(\left(1 + z\right) - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      2. +-inverses49.7%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(t - t\right)} - \left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      3. associate--l+49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(t - t\right) - \color{blue}{\left(1 + \left(z - z\right)\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      4. associate--r+49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(\left(t - t\right) - 1\right) - \left(z - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      5. +-inverses49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(\color{blue}{0} - 1\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      6. metadata-eval49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \color{blue}{\left(1 + 0\right)}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      7. +-inverses49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \left(1 + \color{blue}{\left(x - x\right)}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      8. neg-sub049.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(-\left(1 + \left(x - x\right)\right)\right)} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      9. +-inverses49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\left(1 + \color{blue}{0}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      10. metadata-eval49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\color{blue}{1}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      11. metadata-eval49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{-1} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      12. neg-sub049.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{0 - \left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      13. +-inverses49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(t - t\right)} - \left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      14. +-commutative49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(t - t\right) - \color{blue}{\left(\sqrt{z} + \sqrt{1 + z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      15. associate--r+49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(\left(t - t\right) - \sqrt{z}\right) - \sqrt{1 + z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      16. +-inverses49.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(\color{blue}{0} - \sqrt{z}\right) - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      17. neg-sub049.8%

        \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(-\sqrt{z}\right)} - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
    7. Simplified49.8%

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

    if 6.5e15 < y

    1. Initial program 85.3%

      \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
    2. Step-by-step derivation
      1. associate-+l+85.3%

        \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
      2. associate-+l+85.3%

        \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
      3. +-commutative85.3%

        \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
      4. associate-+l+85.3%

        \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
      5. +-commutative85.3%

        \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
      6. associate-+l-52.3%

        \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
    3. Simplified21.1%

      \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
    4. Applied egg-rr17.7%

      \[\leadsto \color{blue}{\frac{\left(1 + \left(x - x\right)\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)\right)\right) + \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)}^{2}\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)\right)\right)}} \]
    5. Step-by-step derivation
      1. Simplified26.7%

        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right)\right)}} \]
      2. Taylor expanded in t around 0 26.7%

        \[\leadsto \frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \color{blue}{-1}\right)\right)\right)} \]
    6. Recombined 2 regimes into one program.
    7. Final simplification39.4%

      \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq 6.5 \cdot 10^{+15}:\\ \;\;\;\;\sqrt{x + 1} - \left(\sqrt{x} + \left(\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right) + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - \sqrt{z + 1}} - \sqrt{y + 1}\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(1, \sqrt{y + 1} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right)\right), \left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left({\left(\sqrt{y + 1} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right)}^{2}\right)\right)}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(\sqrt{y + 1} + \left(\left(\sqrt{y} + -1\right) - \left(\sqrt{z} - \sqrt{z + 1}\right)\right)\right)}\\ \end{array} \]

    Alternative 2: 96.8% accurate, 0.3× speedup?

    \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1}\\ t_2 := \sqrt{y + 1}\\ t_3 := \sqrt{x} + \sqrt{x + 1}\\ t_4 := \sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\\ t_5 := t_1 - \sqrt{z}\\ \frac{\mathsf{fma}\left(1, t_2 + \left(\frac{\left(z + 1\right) - z}{t_1 + \sqrt{z}} + t_4\right), t_3 \cdot \left({\left(t_2 + t_5\right)}^{2} - {t_4}^{2}\right)\right)}{t_3 \cdot \left(t_2 + \left(t_5 + t_4\right)\right)} \end{array} \end{array} \]
    NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
    (FPCore (x y z t)
     :precision binary64
     (let* ((t_1 (sqrt (+ z 1.0)))
            (t_2 (sqrt (+ y 1.0)))
            (t_3 (+ (sqrt x) (sqrt (+ x 1.0))))
            (t_4 (+ (sqrt y) (- (sqrt t) (sqrt (+ t 1.0)))))
            (t_5 (- t_1 (sqrt z))))
       (/
        (fma
         1.0
         (+ t_2 (+ (/ (- (+ z 1.0) z) (+ t_1 (sqrt z))) t_4))
         (* t_3 (- (pow (+ t_2 t_5) 2.0) (pow t_4 2.0))))
        (* t_3 (+ t_2 (+ t_5 t_4))))))
    assert(x < y && y < z && z < t);
    double code(double x, double y, double z, double t) {
    	double t_1 = sqrt((z + 1.0));
    	double t_2 = sqrt((y + 1.0));
    	double t_3 = sqrt(x) + sqrt((x + 1.0));
    	double t_4 = sqrt(y) + (sqrt(t) - sqrt((t + 1.0)));
    	double t_5 = t_1 - sqrt(z);
    	return fma(1.0, (t_2 + ((((z + 1.0) - z) / (t_1 + sqrt(z))) + t_4)), (t_3 * (pow((t_2 + t_5), 2.0) - pow(t_4, 2.0)))) / (t_3 * (t_2 + (t_5 + t_4)));
    }
    
    x, y, z, t = sort([x, y, z, t])
    function code(x, y, z, t)
    	t_1 = sqrt(Float64(z + 1.0))
    	t_2 = sqrt(Float64(y + 1.0))
    	t_3 = Float64(sqrt(x) + sqrt(Float64(x + 1.0)))
    	t_4 = Float64(sqrt(y) + Float64(sqrt(t) - sqrt(Float64(t + 1.0))))
    	t_5 = Float64(t_1 - sqrt(z))
    	return Float64(fma(1.0, Float64(t_2 + Float64(Float64(Float64(Float64(z + 1.0) - z) / Float64(t_1 + sqrt(z))) + t_4)), Float64(t_3 * Float64((Float64(t_2 + t_5) ^ 2.0) - (t_4 ^ 2.0)))) / Float64(t_3 * Float64(t_2 + Float64(t_5 + t_4))))
    end
    
    NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
    code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[x], $MachinePrecision] + N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(N[Sqrt[y], $MachinePrecision] + N[(N[Sqrt[t], $MachinePrecision] - N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[(t$95$1 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, N[(N[(1.0 * N[(t$95$2 + N[(N[(N[(N[(z + 1.0), $MachinePrecision] - z), $MachinePrecision] / N[(t$95$1 + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + t$95$4), $MachinePrecision]), $MachinePrecision] + N[(t$95$3 * N[(N[Power[N[(t$95$2 + t$95$5), $MachinePrecision], 2.0], $MachinePrecision] - N[Power[t$95$4, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(t$95$3 * N[(t$95$2 + N[(t$95$5 + t$95$4), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]
    
    \begin{array}{l}
    [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
    \\
    \begin{array}{l}
    t_1 := \sqrt{z + 1}\\
    t_2 := \sqrt{y + 1}\\
    t_3 := \sqrt{x} + \sqrt{x + 1}\\
    t_4 := \sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\\
    t_5 := t_1 - \sqrt{z}\\
    \frac{\mathsf{fma}\left(1, t_2 + \left(\frac{\left(z + 1\right) - z}{t_1 + \sqrt{z}} + t_4\right), t_3 \cdot \left({\left(t_2 + t_5\right)}^{2} - {t_4}^{2}\right)\right)}{t_3 \cdot \left(t_2 + \left(t_5 + t_4\right)\right)}
    \end{array}
    \end{array}
    
    Derivation
    1. Initial program 91.4%

      \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
    2. Step-by-step derivation
      1. associate-+l+91.4%

        \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
      2. associate-+l+91.4%

        \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
      3. +-commutative91.4%

        \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
      4. associate-+l+91.4%

        \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
      5. +-commutative91.4%

        \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
      6. associate-+l-50.8%

        \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
    3. Simplified36.7%

      \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
    4. Applied egg-rr50.2%

      \[\leadsto \color{blue}{\frac{\left(1 + \left(x - x\right)\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)\right)\right) + \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)}^{2}\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)\right)\right)}} \]
    5. Step-by-step derivation
      1. Simplified56.3%

        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right)\right)}} \]
      2. Step-by-step derivation
        1. flip--36.7%

          \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{1 + z} + \sqrt{z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
        2. add-sqr-sqrt30.2%

          \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(1 + z\right)} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{1 + z} + \sqrt{z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
        3. add-sqr-sqrt36.8%

          \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(1 + z\right) - \color{blue}{z}}{\sqrt{1 + z} + \sqrt{z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
      3. Applied egg-rr56.4%

        \[\leadsto \frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\color{blue}{\frac{\left(1 + z\right) - z}{\sqrt{1 + z} + \sqrt{z}}} + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right)\right)} \]
      4. Final simplification56.4%

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

      Alternative 3: 94.6% accurate, 0.3× speedup?

      \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{x + 1}\\ t_3 := \sqrt{x} + t_2\\ t_4 := \sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\\ t_5 := \sqrt{z + 1}\\ t_6 := t_5 - \sqrt{z}\\ \mathbf{if}\;x \leq 3.3 \cdot 10^{+15}:\\ \;\;\;\;t_2 - \left(\sqrt{x} + \left(t_4 + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - t_5} - t_1\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(1, t_1 + \left(t_6 + t_4\right), t_3 \cdot \left({\left(t_1 + t_6\right)}^{2} - {t_4}^{2}\right)\right)}{t_3 \cdot \left(t_1 + \left(\left(t_5 + \sqrt{y}\right) - \sqrt{z}\right)\right)}\\ \end{array} \end{array} \]
      NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
      (FPCore (x y z t)
       :precision binary64
       (let* ((t_1 (sqrt (+ y 1.0)))
              (t_2 (sqrt (+ x 1.0)))
              (t_3 (+ (sqrt x) t_2))
              (t_4 (+ (sqrt y) (- (sqrt t) (sqrt (+ t 1.0)))))
              (t_5 (sqrt (+ z 1.0)))
              (t_6 (- t_5 (sqrt z))))
         (if (<= x 3.3e+15)
           (-
            t_2
            (+ (sqrt x) (+ t_4 (- (/ (+ (- z z) 1.0) (- (- (sqrt z)) t_5)) t_1))))
           (/
            (fma
             1.0
             (+ t_1 (+ t_6 t_4))
             (* t_3 (- (pow (+ t_1 t_6) 2.0) (pow t_4 2.0))))
            (* t_3 (+ t_1 (- (+ t_5 (sqrt y)) (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((x + 1.0));
      	double t_3 = sqrt(x) + t_2;
      	double t_4 = sqrt(y) + (sqrt(t) - sqrt((t + 1.0)));
      	double t_5 = sqrt((z + 1.0));
      	double t_6 = t_5 - sqrt(z);
      	double tmp;
      	if (x <= 3.3e+15) {
      		tmp = t_2 - (sqrt(x) + (t_4 + ((((z - z) + 1.0) / (-sqrt(z) - t_5)) - t_1)));
      	} else {
      		tmp = fma(1.0, (t_1 + (t_6 + t_4)), (t_3 * (pow((t_1 + t_6), 2.0) - pow(t_4, 2.0)))) / (t_3 * (t_1 + ((t_5 + sqrt(y)) - 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(x + 1.0))
      	t_3 = Float64(sqrt(x) + t_2)
      	t_4 = Float64(sqrt(y) + Float64(sqrt(t) - sqrt(Float64(t + 1.0))))
      	t_5 = sqrt(Float64(z + 1.0))
      	t_6 = Float64(t_5 - sqrt(z))
      	tmp = 0.0
      	if (x <= 3.3e+15)
      		tmp = Float64(t_2 - Float64(sqrt(x) + Float64(t_4 + Float64(Float64(Float64(Float64(z - z) + 1.0) / Float64(Float64(-sqrt(z)) - t_5)) - t_1))));
      	else
      		tmp = Float64(fma(1.0, Float64(t_1 + Float64(t_6 + t_4)), Float64(t_3 * Float64((Float64(t_1 + t_6) ^ 2.0) - (t_4 ^ 2.0)))) / Float64(t_3 * Float64(t_1 + Float64(Float64(t_5 + sqrt(y)) - 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[(x + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[x], $MachinePrecision] + t$95$2), $MachinePrecision]}, Block[{t$95$4 = N[(N[Sqrt[y], $MachinePrecision] + N[(N[Sqrt[t], $MachinePrecision] - N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$6 = N[(t$95$5 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 3.3e+15], N[(t$95$2 - N[(N[Sqrt[x], $MachinePrecision] + N[(t$95$4 + N[(N[(N[(N[(z - z), $MachinePrecision] + 1.0), $MachinePrecision] / N[((-N[Sqrt[z], $MachinePrecision]) - t$95$5), $MachinePrecision]), $MachinePrecision] - t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 * N[(t$95$1 + N[(t$95$6 + t$95$4), $MachinePrecision]), $MachinePrecision] + N[(t$95$3 * N[(N[Power[N[(t$95$1 + t$95$6), $MachinePrecision], 2.0], $MachinePrecision] - N[Power[t$95$4, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(t$95$3 * N[(t$95$1 + N[(N[(t$95$5 + N[Sqrt[y], $MachinePrecision]), $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]]
      
      \begin{array}{l}
      [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
      \\
      \begin{array}{l}
      t_1 := \sqrt{y + 1}\\
      t_2 := \sqrt{x + 1}\\
      t_3 := \sqrt{x} + t_2\\
      t_4 := \sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\\
      t_5 := \sqrt{z + 1}\\
      t_6 := t_5 - \sqrt{z}\\
      \mathbf{if}\;x \leq 3.3 \cdot 10^{+15}:\\
      \;\;\;\;t_2 - \left(\sqrt{x} + \left(t_4 + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - t_5} - t_1\right)\right)\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;\frac{\mathsf{fma}\left(1, t_1 + \left(t_6 + t_4\right), t_3 \cdot \left({\left(t_1 + t_6\right)}^{2} - {t_4}^{2}\right)\right)}{t_3 \cdot \left(t_1 + \left(\left(t_5 + \sqrt{y}\right) - \sqrt{z}\right)\right)}\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if x < 3.3e15

        1. Initial program 97.3%

          \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        2. Step-by-step derivation
          1. associate-+l+97.3%

            \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
          2. associate-+l+97.3%

            \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
          3. +-commutative97.3%

            \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
          4. associate-+l+97.3%

            \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
          5. +-commutative97.3%

            \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
          6. associate-+l-97.3%

            \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
        3. Simplified68.0%

          \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
        4. Step-by-step derivation
          1. flip--68.0%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{1 + z} + \sqrt{z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          2. frac-2neg68.0%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          3. add-sqr-sqrt55.3%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\color{blue}{\left(1 + z\right)} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          4. add-sqr-sqrt68.3%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\left(1 + z\right) - \color{blue}{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
        5. Applied egg-rr68.3%

          \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
        6. Step-by-step derivation
          1. neg-sub068.3%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{0 - \left(\left(1 + z\right) - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          2. +-inverses68.3%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(t - t\right)} - \left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          3. associate--l+68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(t - t\right) - \color{blue}{\left(1 + \left(z - z\right)\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          4. associate--r+68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(\left(t - t\right) - 1\right) - \left(z - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          5. +-inverses68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(\color{blue}{0} - 1\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          6. metadata-eval68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \color{blue}{\left(1 + 0\right)}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          7. +-inverses68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \left(1 + \color{blue}{\left(x - x\right)}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          8. neg-sub068.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(-\left(1 + \left(x - x\right)\right)\right)} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          9. +-inverses68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\left(1 + \color{blue}{0}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          10. metadata-eval68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\color{blue}{1}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          11. metadata-eval68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{-1} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          12. neg-sub068.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{0 - \left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          13. +-inverses68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(t - t\right)} - \left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          14. +-commutative68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(t - t\right) - \color{blue}{\left(\sqrt{z} + \sqrt{1 + z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          15. associate--r+68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(\left(t - t\right) - \sqrt{z}\right) - \sqrt{1 + z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          16. +-inverses68.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(\color{blue}{0} - \sqrt{z}\right) - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          17. neg-sub068.4%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(-\sqrt{z}\right)} - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
        7. Simplified68.4%

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

        if 3.3e15 < x

        1. Initial program 86.0%

          \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
        2. Step-by-step derivation
          1. associate-+l+86.0%

            \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
          2. associate-+l+86.0%

            \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
          3. +-commutative86.0%

            \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
          4. associate-+l+86.0%

            \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
          5. +-commutative86.0%

            \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
          6. associate-+l-7.7%

            \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
        3. Simplified7.7%

          \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
        4. Applied egg-rr47.3%

          \[\leadsto \color{blue}{\frac{\left(1 + \left(x - x\right)\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)\right)\right) + \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)}^{2}\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)\right)\right)}} \]
        5. Step-by-step derivation
          1. Simplified52.2%

            \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right)\right)}} \]
          2. Taylor expanded in t around inf 34.6%

            \[\leadsto \frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \color{blue}{\left(\left(\sqrt{y} + \sqrt{1 + z}\right) - \sqrt{z}\right)}\right)} \]
          3. Step-by-step derivation
            1. +-commutative34.6%

              \[\leadsto \frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\color{blue}{\left(\sqrt{1 + z} + \sqrt{y}\right)} - \sqrt{z}\right)\right)} \]
          4. Simplified34.6%

            \[\leadsto \frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \color{blue}{\left(\left(\sqrt{1 + z} + \sqrt{y}\right) - \sqrt{z}\right)}\right)} \]
        6. Recombined 2 regimes into one program.
        7. Final simplification50.8%

          \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 3.3 \cdot 10^{+15}:\\ \;\;\;\;\sqrt{x + 1} - \left(\sqrt{x} + \left(\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right) + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - \sqrt{z + 1}} - \sqrt{y + 1}\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(1, \sqrt{y + 1} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right)\right), \left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left({\left(\sqrt{y + 1} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right)}^{2}\right)\right)}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(\sqrt{y + 1} + \left(\left(\sqrt{z + 1} + \sqrt{y}\right) - \sqrt{z}\right)\right)}\\ \end{array} \]

        Alternative 4: 94.6% accurate, 0.3× speedup?

        \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{x + 1}\\ t_3 := \sqrt{x} + t_2\\ t_4 := \sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\\ t_5 := \sqrt{z + 1}\\ t_6 := t_5 - \sqrt{z}\\ \mathbf{if}\;x \leq 3.3 \cdot 10^{+15}:\\ \;\;\;\;t_2 - \left(\sqrt{x} + \left(t_4 + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - t_5} - t_1\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(1, t_1 + \left(\left(t_5 + \sqrt{y}\right) - \sqrt{z}\right), t_3 \cdot \left({\left(t_1 + t_6\right)}^{2} - {t_4}^{2}\right)\right)}{t_3 \cdot \left(t_1 + \left(t_6 + t_4\right)\right)}\\ \end{array} \end{array} \]
        NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
        (FPCore (x y z t)
         :precision binary64
         (let* ((t_1 (sqrt (+ y 1.0)))
                (t_2 (sqrt (+ x 1.0)))
                (t_3 (+ (sqrt x) t_2))
                (t_4 (+ (sqrt y) (- (sqrt t) (sqrt (+ t 1.0)))))
                (t_5 (sqrt (+ z 1.0)))
                (t_6 (- t_5 (sqrt z))))
           (if (<= x 3.3e+15)
             (-
              t_2
              (+ (sqrt x) (+ t_4 (- (/ (+ (- z z) 1.0) (- (- (sqrt z)) t_5)) t_1))))
             (/
              (fma
               1.0
               (+ t_1 (- (+ t_5 (sqrt y)) (sqrt z)))
               (* t_3 (- (pow (+ t_1 t_6) 2.0) (pow t_4 2.0))))
              (* t_3 (+ t_1 (+ t_6 t_4)))))))
        assert(x < y && y < z && z < t);
        double code(double x, double y, double z, double t) {
        	double t_1 = sqrt((y + 1.0));
        	double t_2 = sqrt((x + 1.0));
        	double t_3 = sqrt(x) + t_2;
        	double t_4 = sqrt(y) + (sqrt(t) - sqrt((t + 1.0)));
        	double t_5 = sqrt((z + 1.0));
        	double t_6 = t_5 - sqrt(z);
        	double tmp;
        	if (x <= 3.3e+15) {
        		tmp = t_2 - (sqrt(x) + (t_4 + ((((z - z) + 1.0) / (-sqrt(z) - t_5)) - t_1)));
        	} else {
        		tmp = fma(1.0, (t_1 + ((t_5 + sqrt(y)) - sqrt(z))), (t_3 * (pow((t_1 + t_6), 2.0) - pow(t_4, 2.0)))) / (t_3 * (t_1 + (t_6 + t_4)));
        	}
        	return tmp;
        }
        
        x, y, z, t = sort([x, y, z, t])
        function code(x, y, z, t)
        	t_1 = sqrt(Float64(y + 1.0))
        	t_2 = sqrt(Float64(x + 1.0))
        	t_3 = Float64(sqrt(x) + t_2)
        	t_4 = Float64(sqrt(y) + Float64(sqrt(t) - sqrt(Float64(t + 1.0))))
        	t_5 = sqrt(Float64(z + 1.0))
        	t_6 = Float64(t_5 - sqrt(z))
        	tmp = 0.0
        	if (x <= 3.3e+15)
        		tmp = Float64(t_2 - Float64(sqrt(x) + Float64(t_4 + Float64(Float64(Float64(Float64(z - z) + 1.0) / Float64(Float64(-sqrt(z)) - t_5)) - t_1))));
        	else
        		tmp = Float64(fma(1.0, Float64(t_1 + Float64(Float64(t_5 + sqrt(y)) - sqrt(z))), Float64(t_3 * Float64((Float64(t_1 + t_6) ^ 2.0) - (t_4 ^ 2.0)))) / Float64(t_3 * Float64(t_1 + Float64(t_6 + t_4))));
        	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[(x + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[x], $MachinePrecision] + t$95$2), $MachinePrecision]}, Block[{t$95$4 = N[(N[Sqrt[y], $MachinePrecision] + N[(N[Sqrt[t], $MachinePrecision] - N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$6 = N[(t$95$5 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 3.3e+15], N[(t$95$2 - N[(N[Sqrt[x], $MachinePrecision] + N[(t$95$4 + N[(N[(N[(N[(z - z), $MachinePrecision] + 1.0), $MachinePrecision] / N[((-N[Sqrt[z], $MachinePrecision]) - t$95$5), $MachinePrecision]), $MachinePrecision] - t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 * N[(t$95$1 + N[(N[(t$95$5 + N[Sqrt[y], $MachinePrecision]), $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$3 * N[(N[Power[N[(t$95$1 + t$95$6), $MachinePrecision], 2.0], $MachinePrecision] - N[Power[t$95$4, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(t$95$3 * N[(t$95$1 + N[(t$95$6 + t$95$4), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]]
        
        \begin{array}{l}
        [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
        \\
        \begin{array}{l}
        t_1 := \sqrt{y + 1}\\
        t_2 := \sqrt{x + 1}\\
        t_3 := \sqrt{x} + t_2\\
        t_4 := \sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\\
        t_5 := \sqrt{z + 1}\\
        t_6 := t_5 - \sqrt{z}\\
        \mathbf{if}\;x \leq 3.3 \cdot 10^{+15}:\\
        \;\;\;\;t_2 - \left(\sqrt{x} + \left(t_4 + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - t_5} - t_1\right)\right)\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\frac{\mathsf{fma}\left(1, t_1 + \left(\left(t_5 + \sqrt{y}\right) - \sqrt{z}\right), t_3 \cdot \left({\left(t_1 + t_6\right)}^{2} - {t_4}^{2}\right)\right)}{t_3 \cdot \left(t_1 + \left(t_6 + t_4\right)\right)}\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < 3.3e15

          1. Initial program 97.3%

            \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          2. Step-by-step derivation
            1. associate-+l+97.3%

              \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
            2. associate-+l+97.3%

              \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
            3. +-commutative97.3%

              \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
            4. associate-+l+97.3%

              \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
            5. +-commutative97.3%

              \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
            6. associate-+l-97.3%

              \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
          3. Simplified68.0%

            \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
          4. Step-by-step derivation
            1. flip--68.0%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{1 + z} + \sqrt{z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            2. frac-2neg68.0%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            3. add-sqr-sqrt55.3%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\color{blue}{\left(1 + z\right)} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            4. add-sqr-sqrt68.3%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\left(1 + z\right) - \color{blue}{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          5. Applied egg-rr68.3%

            \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          6. Step-by-step derivation
            1. neg-sub068.3%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{0 - \left(\left(1 + z\right) - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            2. +-inverses68.3%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(t - t\right)} - \left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            3. associate--l+68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(t - t\right) - \color{blue}{\left(1 + \left(z - z\right)\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            4. associate--r+68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(\left(t - t\right) - 1\right) - \left(z - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            5. +-inverses68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(\color{blue}{0} - 1\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            6. metadata-eval68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \color{blue}{\left(1 + 0\right)}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            7. +-inverses68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \left(1 + \color{blue}{\left(x - x\right)}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            8. neg-sub068.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(-\left(1 + \left(x - x\right)\right)\right)} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            9. +-inverses68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\left(1 + \color{blue}{0}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            10. metadata-eval68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\color{blue}{1}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            11. metadata-eval68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{-1} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            12. neg-sub068.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{0 - \left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            13. +-inverses68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(t - t\right)} - \left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            14. +-commutative68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(t - t\right) - \color{blue}{\left(\sqrt{z} + \sqrt{1 + z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            15. associate--r+68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(\left(t - t\right) - \sqrt{z}\right) - \sqrt{1 + z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            16. +-inverses68.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(\color{blue}{0} - \sqrt{z}\right) - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            17. neg-sub068.4%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(-\sqrt{z}\right)} - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
          7. Simplified68.4%

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

          if 3.3e15 < x

          1. Initial program 86.0%

            \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
          2. Step-by-step derivation
            1. associate-+l+86.0%

              \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
            2. associate-+l+86.0%

              \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
            3. +-commutative86.0%

              \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
            4. associate-+l+86.0%

              \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
            5. +-commutative86.0%

              \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
            6. associate-+l-7.7%

              \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
          3. Simplified7.7%

            \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
          4. Applied egg-rr47.3%

            \[\leadsto \color{blue}{\frac{\left(1 + \left(x - x\right)\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)\right)\right) + \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)}^{2}\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)\right)\right)}} \]
          5. Step-by-step derivation
            1. Simplified52.2%

              \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right)\right)}} \]
            2. Taylor expanded in t around inf 50.1%

              \[\leadsto \frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \color{blue}{\left(\left(\sqrt{y} + \sqrt{1 + z}\right) - \sqrt{z}\right)}, \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right)\right)} \]
            3. Step-by-step derivation
              1. +-commutative34.6%

                \[\leadsto \frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\color{blue}{\left(\sqrt{1 + z} + \sqrt{y}\right)} - \sqrt{z}\right)\right)} \]
            4. Simplified50.1%

              \[\leadsto \frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \color{blue}{\left(\left(\sqrt{1 + z} + \sqrt{y}\right) - \sqrt{z}\right)}, \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right)\right)} \]
          6. Recombined 2 regimes into one program.
          7. Final simplification58.9%

            \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 3.3 \cdot 10^{+15}:\\ \;\;\;\;\sqrt{x + 1} - \left(\sqrt{x} + \left(\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right) + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - \sqrt{z + 1}} - \sqrt{y + 1}\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(1, \sqrt{y + 1} + \left(\left(\sqrt{z + 1} + \sqrt{y}\right) - \sqrt{z}\right), \left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left({\left(\sqrt{y + 1} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right)}^{2}\right)\right)}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(\sqrt{y + 1} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right)\right)\right)}\\ \end{array} \]

          Alternative 5: 95.0% accurate, 0.4× speedup?

          \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{y + 1}\\ t_2 := \sqrt{x + 1}\\ t_3 := \sqrt{x} + t_2\\ t_4 := \sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\\ t_5 := \sqrt{z + 1}\\ t_6 := t_5 - \sqrt{z}\\ t_7 := t_1 + \left(t_6 + t_4\right)\\ \mathbf{if}\;x \leq 3.5 \cdot 10^{-5}:\\ \;\;\;\;t_2 - \left(\sqrt{x} + \left(t_4 + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - t_5} - t_1\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(1, t_7, t_3 \cdot \left({\left(t_1 + t_6\right)}^{2} - y\right)\right)}{t_3 \cdot t_7}\\ \end{array} \end{array} \]
          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 (+ x 1.0)))
                  (t_3 (+ (sqrt x) t_2))
                  (t_4 (+ (sqrt y) (- (sqrt t) (sqrt (+ t 1.0)))))
                  (t_5 (sqrt (+ z 1.0)))
                  (t_6 (- t_5 (sqrt z)))
                  (t_7 (+ t_1 (+ t_6 t_4))))
             (if (<= x 3.5e-5)
               (-
                t_2
                (+ (sqrt x) (+ t_4 (- (/ (+ (- z z) 1.0) (- (- (sqrt z)) t_5)) t_1))))
               (/ (fma 1.0 t_7 (* t_3 (- (pow (+ t_1 t_6) 2.0) y))) (* t_3 t_7)))))
          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((x + 1.0));
          	double t_3 = sqrt(x) + t_2;
          	double t_4 = sqrt(y) + (sqrt(t) - sqrt((t + 1.0)));
          	double t_5 = sqrt((z + 1.0));
          	double t_6 = t_5 - sqrt(z);
          	double t_7 = t_1 + (t_6 + t_4);
          	double tmp;
          	if (x <= 3.5e-5) {
          		tmp = t_2 - (sqrt(x) + (t_4 + ((((z - z) + 1.0) / (-sqrt(z) - t_5)) - t_1)));
          	} else {
          		tmp = fma(1.0, t_7, (t_3 * (pow((t_1 + t_6), 2.0) - y))) / (t_3 * t_7);
          	}
          	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(x + 1.0))
          	t_3 = Float64(sqrt(x) + t_2)
          	t_4 = Float64(sqrt(y) + Float64(sqrt(t) - sqrt(Float64(t + 1.0))))
          	t_5 = sqrt(Float64(z + 1.0))
          	t_6 = Float64(t_5 - sqrt(z))
          	t_7 = Float64(t_1 + Float64(t_6 + t_4))
          	tmp = 0.0
          	if (x <= 3.5e-5)
          		tmp = Float64(t_2 - Float64(sqrt(x) + Float64(t_4 + Float64(Float64(Float64(Float64(z - z) + 1.0) / Float64(Float64(-sqrt(z)) - t_5)) - t_1))));
          	else
          		tmp = Float64(fma(1.0, t_7, Float64(t_3 * Float64((Float64(t_1 + t_6) ^ 2.0) - y))) / Float64(t_3 * t_7));
          	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[(x + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[(N[Sqrt[x], $MachinePrecision] + t$95$2), $MachinePrecision]}, Block[{t$95$4 = N[(N[Sqrt[y], $MachinePrecision] + N[(N[Sqrt[t], $MachinePrecision] - N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$6 = N[(t$95$5 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$7 = N[(t$95$1 + N[(t$95$6 + t$95$4), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 3.5e-5], N[(t$95$2 - N[(N[Sqrt[x], $MachinePrecision] + N[(t$95$4 + N[(N[(N[(N[(z - z), $MachinePrecision] + 1.0), $MachinePrecision] / N[((-N[Sqrt[z], $MachinePrecision]) - t$95$5), $MachinePrecision]), $MachinePrecision] - t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 * t$95$7 + N[(t$95$3 * N[(N[Power[N[(t$95$1 + t$95$6), $MachinePrecision], 2.0], $MachinePrecision] - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(t$95$3 * t$95$7), $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{x + 1}\\
          t_3 := \sqrt{x} + t_2\\
          t_4 := \sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\\
          t_5 := \sqrt{z + 1}\\
          t_6 := t_5 - \sqrt{z}\\
          t_7 := t_1 + \left(t_6 + t_4\right)\\
          \mathbf{if}\;x \leq 3.5 \cdot 10^{-5}:\\
          \;\;\;\;t_2 - \left(\sqrt{x} + \left(t_4 + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - t_5} - t_1\right)\right)\right)\\
          
          \mathbf{else}:\\
          \;\;\;\;\frac{\mathsf{fma}\left(1, t_7, t_3 \cdot \left({\left(t_1 + t_6\right)}^{2} - y\right)\right)}{t_3 \cdot t_7}\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if x < 3.4999999999999997e-5

            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. Step-by-step derivation
              1. associate-+l+97.5%

                \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
              2. associate-+l+97.5%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
              3. +-commutative97.5%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
              4. associate-+l+97.5%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
              5. +-commutative97.5%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
              6. associate-+l-97.5%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
            3. Simplified69.9%

              \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
            4. Step-by-step derivation
              1. flip--69.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{1 + z} + \sqrt{z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              2. frac-2neg69.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              3. add-sqr-sqrt56.7%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\color{blue}{\left(1 + z\right)} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              4. add-sqr-sqrt70.1%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\left(1 + z\right) - \color{blue}{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            5. Applied egg-rr70.1%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            6. Step-by-step derivation
              1. neg-sub070.1%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{0 - \left(\left(1 + z\right) - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              2. +-inverses70.1%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(t - t\right)} - \left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              3. associate--l+70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(t - t\right) - \color{blue}{\left(1 + \left(z - z\right)\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              4. associate--r+70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(\left(t - t\right) - 1\right) - \left(z - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              5. +-inverses70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(\color{blue}{0} - 1\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              6. metadata-eval70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \color{blue}{\left(1 + 0\right)}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              7. +-inverses70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \left(1 + \color{blue}{\left(x - x\right)}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              8. neg-sub070.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(-\left(1 + \left(x - x\right)\right)\right)} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              9. +-inverses70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\left(1 + \color{blue}{0}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              10. metadata-eval70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\color{blue}{1}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              11. metadata-eval70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{-1} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              12. neg-sub070.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{0 - \left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              13. +-inverses70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(t - t\right)} - \left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              14. +-commutative70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(t - t\right) - \color{blue}{\left(\sqrt{z} + \sqrt{1 + z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              15. associate--r+70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(\left(t - t\right) - \sqrt{z}\right) - \sqrt{1 + z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              16. +-inverses70.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(\color{blue}{0} - \sqrt{z}\right) - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              17. neg-sub070.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(-\sqrt{z}\right)} - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            7. Simplified70.2%

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

            if 3.4999999999999997e-5 < x

            1. Initial program 86.1%

              \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. Step-by-step derivation
              1. associate-+l+86.1%

                \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
              2. associate-+l+86.1%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
              3. +-commutative86.1%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
              4. associate-+l+86.1%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
              5. +-commutative86.1%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
              6. associate-+l-10.1%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
            3. Simplified7.9%

              \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
            4. Applied egg-rr46.2%

              \[\leadsto \color{blue}{\frac{\left(1 + \left(x - x\right)\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)\right)\right) + \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)}^{2}\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{t} + \left(\sqrt{y} - \sqrt{1 + t}\right)\right)\right)\right)}} \]
            5. Step-by-step derivation
              1. Simplified51.1%

                \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - {\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)}^{2}\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right)\right)}} \]
              2. Taylor expanded in t around inf 19.5%

                \[\leadsto \frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \color{blue}{\left({\left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{z}\right)}^{2} - y\right)}\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right)\right)} \]
              3. Step-by-step derivation
                1. associate-+r-34.4%

                  \[\leadsto \frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left({\color{blue}{\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}}^{2} - y\right)\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right)\right)} \]
              4. Simplified34.4%

                \[\leadsto \frac{\mathsf{fma}\left(1, \sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right), \left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \color{blue}{\left({\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)}^{2} - y\right)}\right)}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{1 + t}\right)\right)\right)\right)} \]
            6. Recombined 2 regimes into one program.
            7. Final simplification51.1%

              \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 3.5 \cdot 10^{-5}:\\ \;\;\;\;\sqrt{x + 1} - \left(\sqrt{x} + \left(\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right) + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - \sqrt{z + 1}} - \sqrt{y + 1}\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(1, \sqrt{y + 1} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right)\right), \left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left({\left(\sqrt{y + 1} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}^{2} - y\right)\right)}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(\sqrt{y + 1} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right)\right)\right)}\\ \end{array} \]

            Alternative 6: 93.4% accurate, 0.9× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{z + 1}\\ t_2 := \sqrt{x + 1}\\ \mathbf{if}\;t_1 - \sqrt{z} \leq 0.9999995:\\ \;\;\;\;t_2 - \left(\sqrt{x} + \left(\frac{-1}{t_1 + \sqrt{z}} + \left(\sqrt{y} - \sqrt{y + 1}\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(t_2 - \sqrt{x}\right) + \left(\frac{1}{\sqrt{t} + \sqrt{t + 1}} + \left(\left(\left(t_1 + 1\right) - \sqrt{z}\right) - \sqrt{y}\right)\right)\\ \end{array} \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t)
             :precision binary64
             (let* ((t_1 (sqrt (+ z 1.0))) (t_2 (sqrt (+ x 1.0))))
               (if (<= (- t_1 (sqrt z)) 0.9999995)
                 (-
                  t_2
                  (+ (sqrt x) (+ (/ -1.0 (+ t_1 (sqrt z))) (- (sqrt y) (sqrt (+ y 1.0))))))
                 (+
                  (- t_2 (sqrt x))
                  (+
                   (/ 1.0 (+ (sqrt t) (sqrt (+ t 1.0))))
                   (- (- (+ t_1 1.0) (sqrt z)) (sqrt y)))))))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	double t_1 = sqrt((z + 1.0));
            	double t_2 = sqrt((x + 1.0));
            	double tmp;
            	if ((t_1 - sqrt(z)) <= 0.9999995) {
            		tmp = t_2 - (sqrt(x) + ((-1.0 / (t_1 + sqrt(z))) + (sqrt(y) - sqrt((y + 1.0)))));
            	} else {
            		tmp = (t_2 - sqrt(x)) + ((1.0 / (sqrt(t) + sqrt((t + 1.0)))) + (((t_1 + 1.0) - sqrt(z)) - sqrt(y)));
            	}
            	return tmp;
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                real(8), intent (in) :: z
                real(8), intent (in) :: t
                real(8) :: t_1
                real(8) :: t_2
                real(8) :: tmp
                t_1 = sqrt((z + 1.0d0))
                t_2 = sqrt((x + 1.0d0))
                if ((t_1 - sqrt(z)) <= 0.9999995d0) then
                    tmp = t_2 - (sqrt(x) + (((-1.0d0) / (t_1 + sqrt(z))) + (sqrt(y) - sqrt((y + 1.0d0)))))
                else
                    tmp = (t_2 - sqrt(x)) + ((1.0d0 / (sqrt(t) + sqrt((t + 1.0d0)))) + (((t_1 + 1.0d0) - sqrt(z)) - sqrt(y)))
                end if
                code = tmp
            end function
            
            assert x < y && y < z && z < t;
            public static double code(double x, double y, double z, double t) {
            	double t_1 = Math.sqrt((z + 1.0));
            	double t_2 = Math.sqrt((x + 1.0));
            	double tmp;
            	if ((t_1 - Math.sqrt(z)) <= 0.9999995) {
            		tmp = t_2 - (Math.sqrt(x) + ((-1.0 / (t_1 + Math.sqrt(z))) + (Math.sqrt(y) - Math.sqrt((y + 1.0)))));
            	} else {
            		tmp = (t_2 - Math.sqrt(x)) + ((1.0 / (Math.sqrt(t) + Math.sqrt((t + 1.0)))) + (((t_1 + 1.0) - Math.sqrt(z)) - Math.sqrt(y)));
            	}
            	return tmp;
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	t_1 = math.sqrt((z + 1.0))
            	t_2 = math.sqrt((x + 1.0))
            	tmp = 0
            	if (t_1 - math.sqrt(z)) <= 0.9999995:
            		tmp = t_2 - (math.sqrt(x) + ((-1.0 / (t_1 + math.sqrt(z))) + (math.sqrt(y) - math.sqrt((y + 1.0)))))
            	else:
            		tmp = (t_2 - math.sqrt(x)) + ((1.0 / (math.sqrt(t) + math.sqrt((t + 1.0)))) + (((t_1 + 1.0) - math.sqrt(z)) - math.sqrt(y)))
            	return tmp
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	t_1 = sqrt(Float64(z + 1.0))
            	t_2 = sqrt(Float64(x + 1.0))
            	tmp = 0.0
            	if (Float64(t_1 - sqrt(z)) <= 0.9999995)
            		tmp = Float64(t_2 - Float64(sqrt(x) + Float64(Float64(-1.0 / Float64(t_1 + sqrt(z))) + Float64(sqrt(y) - sqrt(Float64(y + 1.0))))));
            	else
            		tmp = Float64(Float64(t_2 - sqrt(x)) + Float64(Float64(1.0 / Float64(sqrt(t) + sqrt(Float64(t + 1.0)))) + Float64(Float64(Float64(t_1 + 1.0) - sqrt(z)) - sqrt(y))));
            	end
            	return tmp
            end
            
            x, y, z, t = num2cell(sort([x, y, z, t])){:}
            function tmp_2 = code(x, y, z, t)
            	t_1 = sqrt((z + 1.0));
            	t_2 = sqrt((x + 1.0));
            	tmp = 0.0;
            	if ((t_1 - sqrt(z)) <= 0.9999995)
            		tmp = t_2 - (sqrt(x) + ((-1.0 / (t_1 + sqrt(z))) + (sqrt(y) - sqrt((y + 1.0)))));
            	else
            		tmp = (t_2 - sqrt(x)) + ((1.0 / (sqrt(t) + sqrt((t + 1.0)))) + (((t_1 + 1.0) - sqrt(z)) - sqrt(y)));
            	end
            	tmp_2 = tmp;
            end
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            code[x_, y_, z_, t_] := Block[{t$95$1 = N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[N[(t$95$1 - N[Sqrt[z], $MachinePrecision]), $MachinePrecision], 0.9999995], N[(t$95$2 - N[(N[Sqrt[x], $MachinePrecision] + N[(N[(-1.0 / N[(t$95$1 + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[y], $MachinePrecision] - N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(t$95$2 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision] + N[(N[(1.0 / N[(N[Sqrt[t], $MachinePrecision] + N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(N[(t$95$1 + 1.0), $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \begin{array}{l}
            t_1 := \sqrt{z + 1}\\
            t_2 := \sqrt{x + 1}\\
            \mathbf{if}\;t_1 - \sqrt{z} \leq 0.9999995:\\
            \;\;\;\;t_2 - \left(\sqrt{x} + \left(\frac{-1}{t_1 + \sqrt{z}} + \left(\sqrt{y} - \sqrt{y + 1}\right)\right)\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;\left(t_2 - \sqrt{x}\right) + \left(\frac{1}{\sqrt{t} + \sqrt{t + 1}} + \left(\left(\left(t_1 + 1\right) - \sqrt{z}\right) - \sqrt{y}\right)\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if (-.f64 (sqrt.f64 (+.f64 z 1)) (sqrt.f64 z)) < 0.999999500000000041

              1. Initial program 86.7%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+86.7%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+86.7%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative86.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
                4. associate-+l+86.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
                5. +-commutative86.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
                6. associate-+l-48.3%

                  \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
              3. Simplified38.4%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
              4. Step-by-step derivation
                1. flip--38.4%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{1 + z} + \sqrt{z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                2. frac-2neg38.4%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                3. add-sqr-sqrt26.3%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\color{blue}{\left(1 + z\right)} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                4. add-sqr-sqrt38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\left(1 + z\right) - \color{blue}{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              5. Applied egg-rr38.7%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              6. Step-by-step derivation
                1. neg-sub038.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{0 - \left(\left(1 + z\right) - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                2. +-inverses38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(t - t\right)} - \left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                3. associate--l+38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(t - t\right) - \color{blue}{\left(1 + \left(z - z\right)\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                4. associate--r+38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(\left(t - t\right) - 1\right) - \left(z - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                5. +-inverses38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(\color{blue}{0} - 1\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                6. metadata-eval38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \color{blue}{\left(1 + 0\right)}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                7. +-inverses38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \left(1 + \color{blue}{\left(x - x\right)}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                8. neg-sub038.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(-\left(1 + \left(x - x\right)\right)\right)} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                9. +-inverses38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\left(1 + \color{blue}{0}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                10. metadata-eval38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\color{blue}{1}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                11. metadata-eval38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{-1} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                12. neg-sub038.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{0 - \left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                13. +-inverses38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(t - t\right)} - \left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                14. +-commutative38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(t - t\right) - \color{blue}{\left(\sqrt{z} + \sqrt{1 + z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                15. associate--r+38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(\left(t - t\right) - \sqrt{z}\right) - \sqrt{1 + z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                16. +-inverses38.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(\color{blue}{0} - \sqrt{z}\right) - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                17. neg-sub038.7%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(-\sqrt{z}\right)} - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              7. Simplified38.7%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-1 - \left(z - z\right)}{\left(-\sqrt{z}\right) - \sqrt{1 + z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              8. Taylor expanded in t around inf 32.0%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \color{blue}{\left(\left(\sqrt{1 + y} + \frac{1}{\sqrt{z} + \sqrt{1 + z}}\right) - \sqrt{y}\right)}\right) \]
              9. Step-by-step derivation
                1. +-commutative32.0%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\color{blue}{\left(\frac{1}{\sqrt{z} + \sqrt{1 + z}} + \sqrt{1 + y}\right)} - \sqrt{y}\right)\right) \]
                2. associate--l+32.8%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \color{blue}{\left(\frac{1}{\sqrt{z} + \sqrt{1 + z}} + \left(\sqrt{1 + y} - \sqrt{y}\right)\right)}\right) \]
                3. +-commutative32.8%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\frac{1}{\color{blue}{\sqrt{1 + z} + \sqrt{z}}} + \left(\sqrt{1 + y} - \sqrt{y}\right)\right)\right) \]
              10. Simplified32.8%

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

              if 0.999999500000000041 < (-.f64 (sqrt.f64 (+.f64 z 1)) (sqrt.f64 z))

              1. Initial program 96.9%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+96.9%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+96.9%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative96.9%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} \]
                4. +-commutative96.9%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) \]
                5. associate-+r+96.9%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right)} \]
                6. sub-neg96.9%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} + \left(-\sqrt{t}\right)\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                7. sub-neg96.9%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} - \sqrt{t}\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                8. +-commutative96.9%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{\color{blue}{1 + t}} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
              3. Simplified63.6%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\left(\sqrt{1 + z} - \left(\sqrt{z} - \sqrt{1 + y}\right)\right) - \sqrt{y}\right)\right)} \]
              4. Taylor expanded in y around 0 53.9%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\color{blue}{\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right)} - \sqrt{y}\right)\right) \]
              5. Step-by-step derivation
                1. flip--53.9%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\frac{\sqrt{1 + t} \cdot \sqrt{1 + t} - \sqrt{t} \cdot \sqrt{t}}{\sqrt{1 + t} + \sqrt{t}}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
                2. div-inv53.9%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{1 + t} \cdot \sqrt{1 + t} - \sqrt{t} \cdot \sqrt{t}\right) \cdot \frac{1}{\sqrt{1 + t} + \sqrt{t}}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
                3. add-sqr-sqrt42.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\color{blue}{\left(1 + t\right)} - \sqrt{t} \cdot \sqrt{t}\right) \cdot \frac{1}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
                4. add-sqr-sqrt54.1%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\left(1 + t\right) - \color{blue}{t}\right) \cdot \frac{1}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
                5. associate--l+54.2%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(1 + \left(t - t\right)\right)} \cdot \frac{1}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
              6. Applied egg-rr54.2%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(1 + \left(t - t\right)\right) \cdot \frac{1}{\sqrt{1 + t} + \sqrt{t}}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
              7. Step-by-step derivation
                1. associate-*r/54.2%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\frac{\left(1 + \left(t - t\right)\right) \cdot 1}{\sqrt{1 + t} + \sqrt{t}}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
                2. +-inverses54.2%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\frac{\left(1 + \color{blue}{0}\right) \cdot 1}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
                3. metadata-eval54.2%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\frac{\color{blue}{1} \cdot 1}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
                4. metadata-eval54.2%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\frac{\color{blue}{1}}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
              8. Simplified54.2%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\frac{1}{\sqrt{1 + t} + \sqrt{t}}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
            3. Recombined 2 regimes into one program.
            4. Final simplification42.8%

              \[\leadsto \begin{array}{l} \mathbf{if}\;\sqrt{z + 1} - \sqrt{z} \leq 0.9999995:\\ \;\;\;\;\sqrt{x + 1} - \left(\sqrt{x} + \left(\frac{-1}{\sqrt{z + 1} + \sqrt{z}} + \left(\sqrt{y} - \sqrt{y + 1}\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\frac{1}{\sqrt{t} + \sqrt{t + 1}} + \left(\left(\left(\sqrt{z + 1} + 1\right) - \sqrt{z}\right) - \sqrt{y}\right)\right)\\ \end{array} \]

            Alternative 7: 93.1% accurate, 1.0× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \sqrt{x + 1} - \left(\sqrt{x} + \left(\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right) + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - \sqrt{z + 1}} - \sqrt{y + 1}\right)\right)\right) \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t)
             :precision binary64
             (-
              (sqrt (+ x 1.0))
              (+
               (sqrt x)
               (+
                (+ (sqrt y) (- (sqrt t) (sqrt (+ t 1.0))))
                (-
                 (/ (+ (- z z) 1.0) (- (- (sqrt z)) (sqrt (+ z 1.0))))
                 (sqrt (+ y 1.0)))))))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	return sqrt((x + 1.0)) - (sqrt(x) + ((sqrt(y) + (sqrt(t) - sqrt((t + 1.0)))) + ((((z - z) + 1.0) / (-sqrt(z) - sqrt((z + 1.0)))) - sqrt((y + 1.0)))));
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                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) + (sqrt(t) - sqrt((t + 1.0d0)))) + ((((z - z) + 1.0d0) / (-sqrt(z) - sqrt((z + 1.0d0)))) - sqrt((y + 1.0d0)))))
            end function
            
            assert x < y && y < z && z < t;
            public static double code(double x, double y, double z, double t) {
            	return Math.sqrt((x + 1.0)) - (Math.sqrt(x) + ((Math.sqrt(y) + (Math.sqrt(t) - Math.sqrt((t + 1.0)))) + ((((z - z) + 1.0) / (-Math.sqrt(z) - Math.sqrt((z + 1.0)))) - Math.sqrt((y + 1.0)))));
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	return math.sqrt((x + 1.0)) - (math.sqrt(x) + ((math.sqrt(y) + (math.sqrt(t) - math.sqrt((t + 1.0)))) + ((((z - z) + 1.0) / (-math.sqrt(z) - math.sqrt((z + 1.0)))) - math.sqrt((y + 1.0)))))
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	return Float64(sqrt(Float64(x + 1.0)) - Float64(sqrt(x) + Float64(Float64(sqrt(y) + Float64(sqrt(t) - sqrt(Float64(t + 1.0)))) + Float64(Float64(Float64(Float64(z - z) + 1.0) / Float64(Float64(-sqrt(z)) - sqrt(Float64(z + 1.0)))) - sqrt(Float64(y + 1.0))))))
            end
            
            x, y, z, t = num2cell(sort([x, y, z, t])){:}
            function tmp = code(x, y, z, t)
            	tmp = sqrt((x + 1.0)) - (sqrt(x) + ((sqrt(y) + (sqrt(t) - sqrt((t + 1.0)))) + ((((z - z) + 1.0) / (-sqrt(z) - sqrt((z + 1.0)))) - sqrt((y + 1.0)))));
            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[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[(N[(N[Sqrt[y], $MachinePrecision] + N[(N[Sqrt[t], $MachinePrecision] - N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(N[(N[(z - z), $MachinePrecision] + 1.0), $MachinePrecision] / N[((-N[Sqrt[z], $MachinePrecision]) - N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \sqrt{x + 1} - \left(\sqrt{x} + \left(\left(\sqrt{y} + \left(\sqrt{t} - \sqrt{t + 1}\right)\right) + \left(\frac{\left(z - z\right) + 1}{\left(-\sqrt{z}\right) - \sqrt{z + 1}} - \sqrt{y + 1}\right)\right)\right)
            \end{array}
            
            Derivation
            1. Initial program 91.4%

              \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. Step-by-step derivation
              1. associate-+l+91.4%

                \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
              2. associate-+l+91.4%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
              3. +-commutative91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
              4. associate-+l+91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
              5. +-commutative91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
              6. associate-+l-50.8%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
            3. Simplified36.7%

              \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
            4. Step-by-step derivation
              1. flip--36.7%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{1 + z} + \sqrt{z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              2. frac-2neg36.7%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              3. add-sqr-sqrt30.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\color{blue}{\left(1 + z\right)} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              4. add-sqr-sqrt36.8%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\left(1 + z\right) - \color{blue}{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            5. Applied egg-rr36.8%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            6. Step-by-step derivation
              1. neg-sub036.8%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{0 - \left(\left(1 + z\right) - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              2. +-inverses36.8%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(t - t\right)} - \left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              3. associate--l+36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(t - t\right) - \color{blue}{\left(1 + \left(z - z\right)\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              4. associate--r+36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(\left(t - t\right) - 1\right) - \left(z - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              5. +-inverses36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(\color{blue}{0} - 1\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              6. metadata-eval36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \color{blue}{\left(1 + 0\right)}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              7. +-inverses36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \left(1 + \color{blue}{\left(x - x\right)}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              8. neg-sub036.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(-\left(1 + \left(x - x\right)\right)\right)} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              9. +-inverses36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\left(1 + \color{blue}{0}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              10. metadata-eval36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\color{blue}{1}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              11. metadata-eval36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{-1} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              12. neg-sub036.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{0 - \left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              13. +-inverses36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(t - t\right)} - \left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              14. +-commutative36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(t - t\right) - \color{blue}{\left(\sqrt{z} + \sqrt{1 + z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              15. associate--r+36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(\left(t - t\right) - \sqrt{z}\right) - \sqrt{1 + z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              16. +-inverses36.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(\color{blue}{0} - \sqrt{z}\right) - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              17. neg-sub036.9%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(-\sqrt{z}\right)} - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            7. Simplified36.9%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-1 - \left(z - z\right)}{\left(-\sqrt{z}\right) - \sqrt{1 + z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            8. Final simplification36.9%

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

            Alternative 8: 92.6% accurate, 1.0× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \sqrt{x + 1} + \left(\left(\left(\sqrt{y + 1} + \frac{\left(z + 1\right) - z}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\left(\sqrt{t + 1} - \sqrt{t}\right) - \sqrt{y}\right)\right) - \sqrt{x}\right) \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t)
             :precision binary64
             (+
              (sqrt (+ x 1.0))
              (-
               (+
                (+ (sqrt (+ y 1.0)) (/ (- (+ z 1.0) z) (+ (sqrt (+ z 1.0)) (sqrt z))))
                (- (- (sqrt (+ t 1.0)) (sqrt t)) (sqrt y)))
               (sqrt x))))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	return sqrt((x + 1.0)) + (((sqrt((y + 1.0)) + (((z + 1.0) - z) / (sqrt((z + 1.0)) + sqrt(z)))) + ((sqrt((t + 1.0)) - sqrt(t)) - sqrt(y))) - sqrt(x));
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                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((y + 1.0d0)) + (((z + 1.0d0) - z) / (sqrt((z + 1.0d0)) + sqrt(z)))) + ((sqrt((t + 1.0d0)) - sqrt(t)) - sqrt(y))) - sqrt(x))
            end function
            
            assert x < y && y < z && z < t;
            public static double code(double x, double y, double z, double t) {
            	return Math.sqrt((x + 1.0)) + (((Math.sqrt((y + 1.0)) + (((z + 1.0) - z) / (Math.sqrt((z + 1.0)) + Math.sqrt(z)))) + ((Math.sqrt((t + 1.0)) - Math.sqrt(t)) - Math.sqrt(y))) - Math.sqrt(x));
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	return math.sqrt((x + 1.0)) + (((math.sqrt((y + 1.0)) + (((z + 1.0) - z) / (math.sqrt((z + 1.0)) + math.sqrt(z)))) + ((math.sqrt((t + 1.0)) - math.sqrt(t)) - math.sqrt(y))) - math.sqrt(x))
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	return Float64(sqrt(Float64(x + 1.0)) + Float64(Float64(Float64(sqrt(Float64(y + 1.0)) + Float64(Float64(Float64(z + 1.0) - z) / Float64(sqrt(Float64(z + 1.0)) + sqrt(z)))) + Float64(Float64(sqrt(Float64(t + 1.0)) - sqrt(t)) - sqrt(y))) - sqrt(x)))
            end
            
            x, y, z, t = num2cell(sort([x, y, z, t])){:}
            function tmp = code(x, y, z, t)
            	tmp = sqrt((x + 1.0)) + (((sqrt((y + 1.0)) + (((z + 1.0) - z) / (sqrt((z + 1.0)) + sqrt(z)))) + ((sqrt((t + 1.0)) - sqrt(t)) - sqrt(y))) - sqrt(x));
            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[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] + N[(N[(N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] + N[(N[(N[(z + 1.0), $MachinePrecision] - z), $MachinePrecision] / N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \sqrt{x + 1} + \left(\left(\left(\sqrt{y + 1} + \frac{\left(z + 1\right) - z}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\left(\sqrt{t + 1} - \sqrt{t}\right) - \sqrt{y}\right)\right) - \sqrt{x}\right)
            \end{array}
            
            Derivation
            1. Initial program 91.4%

              \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. Step-by-step derivation
              1. associate-+l+91.4%

                \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
              2. associate-+l+91.4%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
              3. +-commutative91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
              4. associate-+l+91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
              5. +-commutative91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
              6. associate-+l-50.8%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
            3. Simplified36.7%

              \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
            4. Step-by-step derivation
              1. flip--36.7%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{1 + z} + \sqrt{z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              2. add-sqr-sqrt30.2%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(1 + z\right)} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{1 + z} + \sqrt{z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              3. add-sqr-sqrt36.8%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(1 + z\right) - \color{blue}{z}}{\sqrt{1 + z} + \sqrt{z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            5. Applied egg-rr36.8%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{\left(1 + z\right) - z}{\sqrt{1 + z} + \sqrt{z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
            6. Final simplification36.8%

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

            Alternative 9: 92.5% accurate, 1.0× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \sqrt{x + 1} + \left(\left(\left(\sqrt{y + 1} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \frac{1}{\sqrt{t} + \sqrt{t + 1}}\right)\right) - \sqrt{x}\right) \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t)
             :precision binary64
             (+
              (sqrt (+ x 1.0))
              (-
               (-
                (+ (sqrt (+ y 1.0)) (- (sqrt (+ z 1.0)) (sqrt z)))
                (- (sqrt y) (/ 1.0 (+ (sqrt t) (sqrt (+ t 1.0))))))
               (sqrt x))))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	return sqrt((x + 1.0)) + (((sqrt((y + 1.0)) + (sqrt((z + 1.0)) - sqrt(z))) - (sqrt(y) - (1.0 / (sqrt(t) + sqrt((t + 1.0)))))) - sqrt(x));
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                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((y + 1.0d0)) + (sqrt((z + 1.0d0)) - sqrt(z))) - (sqrt(y) - (1.0d0 / (sqrt(t) + sqrt((t + 1.0d0)))))) - sqrt(x))
            end function
            
            assert x < y && y < z && z < t;
            public static double code(double x, double y, double z, double t) {
            	return Math.sqrt((x + 1.0)) + (((Math.sqrt((y + 1.0)) + (Math.sqrt((z + 1.0)) - Math.sqrt(z))) - (Math.sqrt(y) - (1.0 / (Math.sqrt(t) + Math.sqrt((t + 1.0)))))) - Math.sqrt(x));
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	return math.sqrt((x + 1.0)) + (((math.sqrt((y + 1.0)) + (math.sqrt((z + 1.0)) - math.sqrt(z))) - (math.sqrt(y) - (1.0 / (math.sqrt(t) + math.sqrt((t + 1.0)))))) - math.sqrt(x))
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	return Float64(sqrt(Float64(x + 1.0)) + Float64(Float64(Float64(sqrt(Float64(y + 1.0)) + Float64(sqrt(Float64(z + 1.0)) - sqrt(z))) - Float64(sqrt(y) - Float64(1.0 / Float64(sqrt(t) + sqrt(Float64(t + 1.0)))))) - sqrt(x)))
            end
            
            x, y, z, t = num2cell(sort([x, y, z, t])){:}
            function tmp = code(x, y, z, t)
            	tmp = sqrt((x + 1.0)) + (((sqrt((y + 1.0)) + (sqrt((z + 1.0)) - sqrt(z))) - (sqrt(y) - (1.0 / (sqrt(t) + sqrt((t + 1.0)))))) - sqrt(x));
            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[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] + N[(N[(N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] + N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[Sqrt[y], $MachinePrecision] - N[(1.0 / N[(N[Sqrt[t], $MachinePrecision] + N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \sqrt{x + 1} + \left(\left(\left(\sqrt{y + 1} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \frac{1}{\sqrt{t} + \sqrt{t + 1}}\right)\right) - \sqrt{x}\right)
            \end{array}
            
            Derivation
            1. Initial program 91.4%

              \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. Step-by-step derivation
              1. associate-+l+91.4%

                \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
              2. associate-+l+91.4%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
              3. +-commutative91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
              4. associate-+l+91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
              5. +-commutative91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
              6. associate-+l-50.8%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
            3. Simplified36.7%

              \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
            4. Step-by-step derivation
              1. flip--30.8%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\frac{\sqrt{1 + t} \cdot \sqrt{1 + t} - \sqrt{t} \cdot \sqrt{t}}{\sqrt{1 + t} + \sqrt{t}}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
              2. div-inv30.8%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{1 + t} \cdot \sqrt{1 + t} - \sqrt{t} \cdot \sqrt{t}\right) \cdot \frac{1}{\sqrt{1 + t} + \sqrt{t}}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
              3. add-sqr-sqrt24.5%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\color{blue}{\left(1 + t\right)} - \sqrt{t} \cdot \sqrt{t}\right) \cdot \frac{1}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
              4. add-sqr-sqrt30.9%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\left(1 + t\right) - \color{blue}{t}\right) \cdot \frac{1}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
              5. associate--l+31.2%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(1 + \left(t - t\right)\right)} \cdot \frac{1}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
            5. Applied egg-rr36.8%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \color{blue}{\left(1 + \left(t - t\right)\right) \cdot \frac{1}{\sqrt{1 + t} + \sqrt{t}}}\right)\right)\right) \]
            6. Step-by-step derivation
              1. associate-*r/31.2%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\frac{\left(1 + \left(t - t\right)\right) \cdot 1}{\sqrt{1 + t} + \sqrt{t}}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
              2. +-inverses31.2%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\frac{\left(1 + \color{blue}{0}\right) \cdot 1}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
              3. metadata-eval31.2%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\frac{\color{blue}{1} \cdot 1}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
              4. metadata-eval31.2%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\frac{\color{blue}{1}}{\sqrt{1 + t} + \sqrt{t}} + \left(\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)\right) \]
            7. Simplified36.8%

              \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \color{blue}{\frac{1}{\sqrt{1 + t} + \sqrt{t}}}\right)\right)\right) \]
            8. Final simplification36.8%

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

            Alternative 10: 92.9% accurate, 1.3× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} \mathbf{if}\;t \leq 2.15 \cdot 10^{+17}:\\ \;\;\;\;\left(\sqrt{t + 1} + 3\right) - \left(\sqrt{y} + \sqrt{t}\right)\\ \mathbf{else}:\\ \;\;\;\;\sqrt{x + 1} - \left(\sqrt{x} + \left(\frac{-1}{\sqrt{z + 1} + \sqrt{z}} + \left(\sqrt{y} - \sqrt{y + 1}\right)\right)\right)\\ \end{array} \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t)
             :precision binary64
             (if (<= t 2.15e+17)
               (- (+ (sqrt (+ t 1.0)) 3.0) (+ (sqrt y) (sqrt t)))
               (-
                (sqrt (+ x 1.0))
                (+
                 (sqrt x)
                 (+
                  (/ -1.0 (+ (sqrt (+ z 1.0)) (sqrt z)))
                  (- (sqrt y) (sqrt (+ y 1.0))))))))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	double tmp;
            	if (t <= 2.15e+17) {
            		tmp = (sqrt((t + 1.0)) + 3.0) - (sqrt(y) + sqrt(t));
            	} else {
            		tmp = sqrt((x + 1.0)) - (sqrt(x) + ((-1.0 / (sqrt((z + 1.0)) + sqrt(z))) + (sqrt(y) - sqrt((y + 1.0)))));
            	}
            	return tmp;
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                real(8), intent (in) :: z
                real(8), intent (in) :: t
                real(8) :: tmp
                if (t <= 2.15d+17) then
                    tmp = (sqrt((t + 1.0d0)) + 3.0d0) - (sqrt(y) + sqrt(t))
                else
                    tmp = sqrt((x + 1.0d0)) - (sqrt(x) + (((-1.0d0) / (sqrt((z + 1.0d0)) + sqrt(z))) + (sqrt(y) - sqrt((y + 1.0d0)))))
                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 (t <= 2.15e+17) {
            		tmp = (Math.sqrt((t + 1.0)) + 3.0) - (Math.sqrt(y) + Math.sqrt(t));
            	} else {
            		tmp = Math.sqrt((x + 1.0)) - (Math.sqrt(x) + ((-1.0 / (Math.sqrt((z + 1.0)) + Math.sqrt(z))) + (Math.sqrt(y) - Math.sqrt((y + 1.0)))));
            	}
            	return tmp;
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	tmp = 0
            	if t <= 2.15e+17:
            		tmp = (math.sqrt((t + 1.0)) + 3.0) - (math.sqrt(y) + math.sqrt(t))
            	else:
            		tmp = math.sqrt((x + 1.0)) - (math.sqrt(x) + ((-1.0 / (math.sqrt((z + 1.0)) + math.sqrt(z))) + (math.sqrt(y) - math.sqrt((y + 1.0)))))
            	return tmp
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	tmp = 0.0
            	if (t <= 2.15e+17)
            		tmp = Float64(Float64(sqrt(Float64(t + 1.0)) + 3.0) - Float64(sqrt(y) + sqrt(t)));
            	else
            		tmp = Float64(sqrt(Float64(x + 1.0)) - Float64(sqrt(x) + Float64(Float64(-1.0 / Float64(sqrt(Float64(z + 1.0)) + sqrt(z))) + Float64(sqrt(y) - sqrt(Float64(y + 1.0))))));
            	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 (t <= 2.15e+17)
            		tmp = (sqrt((t + 1.0)) + 3.0) - (sqrt(y) + sqrt(t));
            	else
            		tmp = sqrt((x + 1.0)) - (sqrt(x) + ((-1.0 / (sqrt((z + 1.0)) + sqrt(z))) + (sqrt(y) - sqrt((y + 1.0)))));
            	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[t, 2.15e+17], N[(N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] + 3.0), $MachinePrecision] - N[(N[Sqrt[y], $MachinePrecision] + N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[(N[Sqrt[x], $MachinePrecision] + N[(N[(-1.0 / N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[y], $MachinePrecision] - N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \begin{array}{l}
            \mathbf{if}\;t \leq 2.15 \cdot 10^{+17}:\\
            \;\;\;\;\left(\sqrt{t + 1} + 3\right) - \left(\sqrt{y} + \sqrt{t}\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;\sqrt{x + 1} - \left(\sqrt{x} + \left(\frac{-1}{\sqrt{z + 1} + \sqrt{z}} + \left(\sqrt{y} - \sqrt{y + 1}\right)\right)\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if t < 2.15e17

              1. Initial program 95.7%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+95.7%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+95.7%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} \]
                4. +-commutative95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) \]
                5. associate-+r+95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right)} \]
                6. sub-neg95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} + \left(-\sqrt{t}\right)\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                7. sub-neg95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} - \sqrt{t}\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                8. +-commutative95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{\color{blue}{1 + t}} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
              3. Simplified51.6%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\left(\sqrt{1 + z} - \left(\sqrt{z} - \sqrt{1 + y}\right)\right) - \sqrt{y}\right)\right)} \]
              4. Taylor expanded in y around 0 31.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\color{blue}{\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right)} - \sqrt{y}\right)\right) \]
              5. Taylor expanded in x around 0 17.2%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \left(\sqrt{t} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              6. Step-by-step derivation
                1. associate-+r+17.2%

                  \[\leadsto \left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \color{blue}{\left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right)} \]
                2. +-commutative17.2%

                  \[\leadsto \left(2 + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + t}\right)}\right) - \left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right) \]
                3. +-commutative17.2%

                  \[\leadsto \left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \color{blue}{\left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              7. Simplified17.2%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              8. Taylor expanded in z around 0 19.7%

                \[\leadsto \color{blue}{\left(3 + \sqrt{1 + t}\right) - \left(\sqrt{t} + \sqrt{y}\right)} \]

              if 2.15e17 < t

              1. Initial program 86.6%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+86.6%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+86.6%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative86.6%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
                4. associate-+l+86.6%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
                5. +-commutative86.6%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
                6. associate-+l-50.6%

                  \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
              3. Simplified45.3%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
              4. Step-by-step derivation
                1. flip--45.3%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}}{\sqrt{1 + z} + \sqrt{z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                2. frac-2neg45.3%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\sqrt{1 + z} \cdot \sqrt{1 + z} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                3. add-sqr-sqrt35.5%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\color{blue}{\left(1 + z\right)} - \sqrt{z} \cdot \sqrt{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                4. add-sqr-sqrt45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-\left(\left(1 + z\right) - \color{blue}{z}\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              5. Applied egg-rr45.6%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-\left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              6. Step-by-step derivation
                1. neg-sub045.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{0 - \left(\left(1 + z\right) - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                2. +-inverses45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(t - t\right)} - \left(\left(1 + z\right) - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                3. associate--l+45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(t - t\right) - \color{blue}{\left(1 + \left(z - z\right)\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                4. associate--r+45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(\left(t - t\right) - 1\right) - \left(z - z\right)}}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                5. +-inverses45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(\color{blue}{0} - 1\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                6. metadata-eval45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \color{blue}{\left(1 + 0\right)}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                7. +-inverses45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(0 - \left(1 + \color{blue}{\left(x - x\right)}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                8. neg-sub045.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{\left(-\left(1 + \left(x - x\right)\right)\right)} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                9. +-inverses45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\left(1 + \color{blue}{0}\right)\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                10. metadata-eval45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\left(-\color{blue}{1}\right) - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                11. metadata-eval45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{\color{blue}{-1} - \left(z - z\right)}{-\left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                12. neg-sub045.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{0 - \left(\sqrt{1 + z} + \sqrt{z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                13. +-inverses45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(t - t\right)} - \left(\sqrt{1 + z} + \sqrt{z}\right)}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                14. +-commutative45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(t - t\right) - \color{blue}{\left(\sqrt{z} + \sqrt{1 + z}\right)}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                15. associate--r+45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(\left(t - t\right) - \sqrt{z}\right) - \sqrt{1 + z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                16. +-inverses45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\left(\color{blue}{0} - \sqrt{z}\right) - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
                17. neg-sub045.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \frac{-1 - \left(z - z\right)}{\color{blue}{\left(-\sqrt{z}\right)} - \sqrt{1 + z}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              7. Simplified45.6%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \color{blue}{\frac{-1 - \left(z - z\right)}{\left(-\sqrt{z}\right) - \sqrt{1 + z}}}\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right) \]
              8. Taylor expanded in t around inf 45.6%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \color{blue}{\left(\left(\sqrt{1 + y} + \frac{1}{\sqrt{z} + \sqrt{1 + z}}\right) - \sqrt{y}\right)}\right) \]
              9. Step-by-step derivation
                1. +-commutative45.6%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\color{blue}{\left(\frac{1}{\sqrt{z} + \sqrt{1 + z}} + \sqrt{1 + y}\right)} - \sqrt{y}\right)\right) \]
                2. associate--l+51.3%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \color{blue}{\left(\frac{1}{\sqrt{z} + \sqrt{1 + z}} + \left(\sqrt{1 + y} - \sqrt{y}\right)\right)}\right) \]
                3. +-commutative51.3%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\frac{1}{\color{blue}{\sqrt{1 + z} + \sqrt{z}}} + \left(\sqrt{1 + y} - \sqrt{y}\right)\right)\right) \]
              10. Simplified51.3%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \color{blue}{\left(\frac{1}{\sqrt{1 + z} + \sqrt{z}} + \left(\sqrt{1 + y} - \sqrt{y}\right)\right)}\right) \]
            3. Recombined 2 regimes into one program.
            4. Final simplification34.5%

              \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 2.15 \cdot 10^{+17}:\\ \;\;\;\;\left(\sqrt{t + 1} + 3\right) - \left(\sqrt{y} + \sqrt{t}\right)\\ \mathbf{else}:\\ \;\;\;\;\sqrt{x + 1} - \left(\sqrt{x} + \left(\frac{-1}{\sqrt{z + 1} + \sqrt{z}} + \left(\sqrt{y} - \sqrt{y + 1}\right)\right)\right)\\ \end{array} \]

            Alternative 11: 91.8% accurate, 1.3× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} \mathbf{if}\;t \leq 5 \cdot 10^{+18}:\\ \;\;\;\;\left(\sqrt{t + 1} + 3\right) - \left(\sqrt{y} + \sqrt{t}\right)\\ \mathbf{else}:\\ \;\;\;\;\sqrt{x + 1} + \left(\left(\sqrt{y + 1} - \left(\sqrt{y} + \left(\sqrt{z} - \sqrt{z + 1}\right)\right)\right) - \sqrt{x}\right)\\ \end{array} \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t)
             :precision binary64
             (if (<= t 5e+18)
               (- (+ (sqrt (+ t 1.0)) 3.0) (+ (sqrt y) (sqrt t)))
               (+
                (sqrt (+ x 1.0))
                (-
                 (- (sqrt (+ y 1.0)) (+ (sqrt y) (- (sqrt z) (sqrt (+ z 1.0)))))
                 (sqrt x)))))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	double tmp;
            	if (t <= 5e+18) {
            		tmp = (sqrt((t + 1.0)) + 3.0) - (sqrt(y) + sqrt(t));
            	} else {
            		tmp = sqrt((x + 1.0)) + ((sqrt((y + 1.0)) - (sqrt(y) + (sqrt(z) - sqrt((z + 1.0))))) - sqrt(x));
            	}
            	return tmp;
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                real(8), intent (in) :: z
                real(8), intent (in) :: t
                real(8) :: tmp
                if (t <= 5d+18) then
                    tmp = (sqrt((t + 1.0d0)) + 3.0d0) - (sqrt(y) + sqrt(t))
                else
                    tmp = sqrt((x + 1.0d0)) + ((sqrt((y + 1.0d0)) - (sqrt(y) + (sqrt(z) - sqrt((z + 1.0d0))))) - 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 (t <= 5e+18) {
            		tmp = (Math.sqrt((t + 1.0)) + 3.0) - (Math.sqrt(y) + Math.sqrt(t));
            	} else {
            		tmp = Math.sqrt((x + 1.0)) + ((Math.sqrt((y + 1.0)) - (Math.sqrt(y) + (Math.sqrt(z) - Math.sqrt((z + 1.0))))) - Math.sqrt(x));
            	}
            	return tmp;
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	tmp = 0
            	if t <= 5e+18:
            		tmp = (math.sqrt((t + 1.0)) + 3.0) - (math.sqrt(y) + math.sqrt(t))
            	else:
            		tmp = math.sqrt((x + 1.0)) + ((math.sqrt((y + 1.0)) - (math.sqrt(y) + (math.sqrt(z) - math.sqrt((z + 1.0))))) - math.sqrt(x))
            	return tmp
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	tmp = 0.0
            	if (t <= 5e+18)
            		tmp = Float64(Float64(sqrt(Float64(t + 1.0)) + 3.0) - Float64(sqrt(y) + sqrt(t)));
            	else
            		tmp = Float64(sqrt(Float64(x + 1.0)) + Float64(Float64(sqrt(Float64(y + 1.0)) - Float64(sqrt(y) + Float64(sqrt(z) - sqrt(Float64(z + 1.0))))) - 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 (t <= 5e+18)
            		tmp = (sqrt((t + 1.0)) + 3.0) - (sqrt(y) + sqrt(t));
            	else
            		tmp = sqrt((x + 1.0)) + ((sqrt((y + 1.0)) - (sqrt(y) + (sqrt(z) - sqrt((z + 1.0))))) - 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[t, 5e+18], N[(N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] + 3.0), $MachinePrecision] - N[(N[Sqrt[y], $MachinePrecision] + N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] + N[(N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[(N[Sqrt[y], $MachinePrecision] + N[(N[Sqrt[z], $MachinePrecision] - N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \begin{array}{l}
            \mathbf{if}\;t \leq 5 \cdot 10^{+18}:\\
            \;\;\;\;\left(\sqrt{t + 1} + 3\right) - \left(\sqrt{y} + \sqrt{t}\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;\sqrt{x + 1} + \left(\left(\sqrt{y + 1} - \left(\sqrt{y} + \left(\sqrt{z} - \sqrt{z + 1}\right)\right)\right) - \sqrt{x}\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if t < 5e18

              1. Initial program 95.7%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+95.7%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+95.7%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} \]
                4. +-commutative95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) \]
                5. associate-+r+95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right)} \]
                6. sub-neg95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} + \left(-\sqrt{t}\right)\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                7. sub-neg95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} - \sqrt{t}\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                8. +-commutative95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{\color{blue}{1 + t}} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
              3. Simplified51.6%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\left(\sqrt{1 + z} - \left(\sqrt{z} - \sqrt{1 + y}\right)\right) - \sqrt{y}\right)\right)} \]
              4. Taylor expanded in y around 0 31.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\color{blue}{\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right)} - \sqrt{y}\right)\right) \]
              5. Taylor expanded in x around 0 17.2%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \left(\sqrt{t} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              6. Step-by-step derivation
                1. associate-+r+17.2%

                  \[\leadsto \left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \color{blue}{\left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right)} \]
                2. +-commutative17.2%

                  \[\leadsto \left(2 + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + t}\right)}\right) - \left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right) \]
                3. +-commutative17.2%

                  \[\leadsto \left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \color{blue}{\left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              7. Simplified17.2%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              8. Taylor expanded in z around 0 19.7%

                \[\leadsto \color{blue}{\left(3 + \sqrt{1 + t}\right) - \left(\sqrt{t} + \sqrt{y}\right)} \]

              if 5e18 < t

              1. Initial program 86.6%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+86.6%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+86.6%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative86.6%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
                4. associate-+l+86.6%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
                5. +-commutative86.6%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
                6. associate-+l-50.6%

                  \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
              3. Simplified45.3%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
              4. Taylor expanded in t around inf 31.8%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \color{blue}{\left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\sqrt{y} + \sqrt{z}\right)\right)}\right) \]
              5. Step-by-step derivation
                1. associate--l+39.9%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \color{blue}{\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \left(\sqrt{y} + \sqrt{z}\right)\right)\right)}\right) \]
                2. +-commutative39.9%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \color{blue}{\left(\sqrt{z} + \sqrt{y}\right)}\right)\right)\right) \]
                3. associate--l-45.3%

                  \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \left(\sqrt{1 + y} + \color{blue}{\left(\left(\sqrt{1 + z} - \sqrt{z}\right) - \sqrt{y}\right)}\right)\right) \]
              6. Simplified45.3%

                \[\leadsto \sqrt{x + 1} - \left(\sqrt{x} - \color{blue}{\left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) - \sqrt{y}\right)\right)}\right) \]
            3. Recombined 2 regimes into one program.
            4. Final simplification31.7%

              \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 5 \cdot 10^{+18}:\\ \;\;\;\;\left(\sqrt{t + 1} + 3\right) - \left(\sqrt{y} + \sqrt{t}\right)\\ \mathbf{else}:\\ \;\;\;\;\sqrt{x + 1} + \left(\left(\sqrt{y + 1} - \left(\sqrt{y} + \left(\sqrt{z} - \sqrt{z + 1}\right)\right)\right) - \sqrt{x}\right)\\ \end{array} \]

            Alternative 12: 90.5% accurate, 2.0× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} \mathbf{if}\;t \leq 5 \cdot 10^{+18}:\\ \;\;\;\;\left(\sqrt{t + 1} + 3\right) - \left(\sqrt{y} + \sqrt{t}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\sqrt{y + 1} - \left(\sqrt{y} + \left(\sqrt{z} - \sqrt{z + 1}\right)\right)\right) + 1\\ \end{array} \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t)
             :precision binary64
             (if (<= t 5e+18)
               (- (+ (sqrt (+ t 1.0)) 3.0) (+ (sqrt y) (sqrt t)))
               (+ (- (sqrt (+ y 1.0)) (+ (sqrt y) (- (sqrt z) (sqrt (+ z 1.0))))) 1.0)))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	double tmp;
            	if (t <= 5e+18) {
            		tmp = (sqrt((t + 1.0)) + 3.0) - (sqrt(y) + sqrt(t));
            	} else {
            		tmp = (sqrt((y + 1.0)) - (sqrt(y) + (sqrt(z) - sqrt((z + 1.0))))) + 1.0;
            	}
            	return tmp;
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                real(8), intent (in) :: z
                real(8), intent (in) :: t
                real(8) :: tmp
                if (t <= 5d+18) then
                    tmp = (sqrt((t + 1.0d0)) + 3.0d0) - (sqrt(y) + sqrt(t))
                else
                    tmp = (sqrt((y + 1.0d0)) - (sqrt(y) + (sqrt(z) - sqrt((z + 1.0d0))))) + 1.0d0
                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 (t <= 5e+18) {
            		tmp = (Math.sqrt((t + 1.0)) + 3.0) - (Math.sqrt(y) + Math.sqrt(t));
            	} else {
            		tmp = (Math.sqrt((y + 1.0)) - (Math.sqrt(y) + (Math.sqrt(z) - Math.sqrt((z + 1.0))))) + 1.0;
            	}
            	return tmp;
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	tmp = 0
            	if t <= 5e+18:
            		tmp = (math.sqrt((t + 1.0)) + 3.0) - (math.sqrt(y) + math.sqrt(t))
            	else:
            		tmp = (math.sqrt((y + 1.0)) - (math.sqrt(y) + (math.sqrt(z) - math.sqrt((z + 1.0))))) + 1.0
            	return tmp
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	tmp = 0.0
            	if (t <= 5e+18)
            		tmp = Float64(Float64(sqrt(Float64(t + 1.0)) + 3.0) - Float64(sqrt(y) + sqrt(t)));
            	else
            		tmp = Float64(Float64(sqrt(Float64(y + 1.0)) - Float64(sqrt(y) + Float64(sqrt(z) - sqrt(Float64(z + 1.0))))) + 1.0);
            	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 (t <= 5e+18)
            		tmp = (sqrt((t + 1.0)) + 3.0) - (sqrt(y) + sqrt(t));
            	else
            		tmp = (sqrt((y + 1.0)) - (sqrt(y) + (sqrt(z) - sqrt((z + 1.0))))) + 1.0;
            	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[t, 5e+18], N[(N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] + 3.0), $MachinePrecision] - N[(N[Sqrt[y], $MachinePrecision] + N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[(N[Sqrt[y], $MachinePrecision] + N[(N[Sqrt[z], $MachinePrecision] - N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \begin{array}{l}
            \mathbf{if}\;t \leq 5 \cdot 10^{+18}:\\
            \;\;\;\;\left(\sqrt{t + 1} + 3\right) - \left(\sqrt{y} + \sqrt{t}\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;\left(\sqrt{y + 1} - \left(\sqrt{y} + \left(\sqrt{z} - \sqrt{z + 1}\right)\right)\right) + 1\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if t < 5e18

              1. Initial program 95.7%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+95.7%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+95.7%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} \]
                4. +-commutative95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) \]
                5. associate-+r+95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right)} \]
                6. sub-neg95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} + \left(-\sqrt{t}\right)\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                7. sub-neg95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} - \sqrt{t}\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                8. +-commutative95.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{\color{blue}{1 + t}} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
              3. Simplified51.6%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\left(\sqrt{1 + z} - \left(\sqrt{z} - \sqrt{1 + y}\right)\right) - \sqrt{y}\right)\right)} \]
              4. Taylor expanded in y around 0 31.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\color{blue}{\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right)} - \sqrt{y}\right)\right) \]
              5. Taylor expanded in x around 0 17.2%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \left(\sqrt{t} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              6. Step-by-step derivation
                1. associate-+r+17.2%

                  \[\leadsto \left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \color{blue}{\left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right)} \]
                2. +-commutative17.2%

                  \[\leadsto \left(2 + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + t}\right)}\right) - \left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right) \]
                3. +-commutative17.2%

                  \[\leadsto \left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \color{blue}{\left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              7. Simplified17.2%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              8. Taylor expanded in z around 0 19.7%

                \[\leadsto \color{blue}{\left(3 + \sqrt{1 + t}\right) - \left(\sqrt{t} + \sqrt{y}\right)} \]

              if 5e18 < t

              1. Initial program 86.6%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+86.6%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+86.6%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative86.6%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
                4. associate-+l+86.6%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
                5. +-commutative86.6%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
                6. associate-+l-50.6%

                  \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
              3. Simplified45.3%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
              4. Taylor expanded in t around inf 17.8%

                \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              5. Step-by-step derivation
                1. +-commutative17.8%

                  \[\leadsto \left(\sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + y}\right)}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right) \]
                2. associate--l+31.6%

                  \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + z} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right)} \]
                3. +-commutative31.6%

                  \[\leadsto \sqrt{1 + x} + \left(\color{blue}{\left(\sqrt{1 + y} + \sqrt{1 + z}\right)} - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right) \]
                4. +-commutative31.6%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \color{blue}{\left(\left(\sqrt{y} + \sqrt{z}\right) + \sqrt{x}\right)}\right) \]
                5. +-commutative31.6%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\color{blue}{\left(\sqrt{z} + \sqrt{y}\right)} + \sqrt{x}\right)\right) \]
              6. Simplified31.6%

                \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\left(\sqrt{z} + \sqrt{y}\right) + \sqrt{x}\right)\right)} \]
              7. Step-by-step derivation
                1. +-commutative31.6%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\left(\sqrt{z} + \sqrt{y}\right) + \sqrt{x}\right)\right) + \sqrt{1 + x}} \]
                2. associate--r+31.8%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\sqrt{z} + \sqrt{y}\right)\right) - \sqrt{x}\right)} + \sqrt{1 + x} \]
                3. associate-+l-45.1%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\sqrt{z} + \sqrt{y}\right)\right) - \left(\sqrt{x} - \sqrt{1 + x}\right)} \]
                4. associate--r+39.3%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)} - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
                5. associate-+r-71.4%

                  \[\leadsto \left(\color{blue}{\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)} - \sqrt{y}\right) - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
                6. +-commutative71.4%

                  \[\leadsto \left(\color{blue}{\left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \sqrt{1 + y}\right)} - \sqrt{y}\right) - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
                7. associate-+l-39.3%

                  \[\leadsto \left(\color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{z} - \sqrt{1 + y}\right)\right)} - \sqrt{y}\right) - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
                8. associate--r+53.5%

                  \[\leadsto \color{blue}{\left(\sqrt{1 + z} - \left(\left(\sqrt{z} - \sqrt{1 + y}\right) + \sqrt{y}\right)\right)} - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
                9. +-commutative53.5%

                  \[\leadsto \left(\sqrt{1 + z} - \color{blue}{\left(\sqrt{y} + \left(\sqrt{z} - \sqrt{1 + y}\right)\right)}\right) - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
              8. Applied egg-rr53.5%

                \[\leadsto \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{y} + \left(\sqrt{z} - \sqrt{1 + y}\right)\right)\right) - \left(\sqrt{x} - \sqrt{1 + x}\right)} \]
              9. Taylor expanded in x around 0 20.0%

                \[\leadsto \color{blue}{\left(1 + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{y} + \sqrt{z}\right)} \]
              10. Step-by-step derivation
                1. associate--l+56.3%

                  \[\leadsto \color{blue}{1 + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
                2. associate--l+51.4%

                  \[\leadsto 1 + \color{blue}{\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \left(\sqrt{y} + \sqrt{z}\right)\right)\right)} \]
                3. +-commutative51.4%

                  \[\leadsto 1 + \left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \color{blue}{\left(\sqrt{z} + \sqrt{y}\right)}\right)\right) \]
                4. associate--r+56.6%

                  \[\leadsto 1 + \left(\sqrt{1 + y} + \color{blue}{\left(\left(\sqrt{1 + z} - \sqrt{z}\right) - \sqrt{y}\right)}\right) \]
              11. Simplified56.6%

                \[\leadsto \color{blue}{1 + \left(\sqrt{1 + y} + \left(\left(\sqrt{1 + z} - \sqrt{z}\right) - \sqrt{y}\right)\right)} \]
            3. Recombined 2 regimes into one program.
            4. Final simplification37.0%

              \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 5 \cdot 10^{+18}:\\ \;\;\;\;\left(\sqrt{t + 1} + 3\right) - \left(\sqrt{y} + \sqrt{t}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\sqrt{y + 1} - \left(\sqrt{y} + \left(\sqrt{z} - \sqrt{z + 1}\right)\right)\right) + 1\\ \end{array} \]

            Alternative 13: 84.7% accurate, 2.0× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} \mathbf{if}\;z \leq 2.8 \cdot 10^{+14}:\\ \;\;\;\;\left(\sqrt{z + 1} + 2\right) - \left(\sqrt{z} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\sqrt{x + 1} + \left(\sqrt{y + 1} - \left(\sqrt{y} + \sqrt{x}\right)\right)\\ \end{array} \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t)
             :precision binary64
             (if (<= z 2.8e+14)
               (- (+ (sqrt (+ z 1.0)) 2.0) (+ (sqrt z) (sqrt y)))
               (+ (sqrt (+ x 1.0)) (- (sqrt (+ y 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 (z <= 2.8e+14) {
            		tmp = (sqrt((z + 1.0)) + 2.0) - (sqrt(z) + sqrt(y));
            	} else {
            		tmp = sqrt((x + 1.0)) + (sqrt((y + 1.0)) - (sqrt(y) + sqrt(x)));
            	}
            	return tmp;
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                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 <= 2.8d+14) then
                    tmp = (sqrt((z + 1.0d0)) + 2.0d0) - (sqrt(z) + sqrt(y))
                else
                    tmp = sqrt((x + 1.0d0)) + (sqrt((y + 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 (z <= 2.8e+14) {
            		tmp = (Math.sqrt((z + 1.0)) + 2.0) - (Math.sqrt(z) + Math.sqrt(y));
            	} else {
            		tmp = Math.sqrt((x + 1.0)) + (Math.sqrt((y + 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 z <= 2.8e+14:
            		tmp = (math.sqrt((z + 1.0)) + 2.0) - (math.sqrt(z) + math.sqrt(y))
            	else:
            		tmp = math.sqrt((x + 1.0)) + (math.sqrt((y + 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 (z <= 2.8e+14)
            		tmp = Float64(Float64(sqrt(Float64(z + 1.0)) + 2.0) - Float64(sqrt(z) + sqrt(y)));
            	else
            		tmp = Float64(sqrt(Float64(x + 1.0)) + Float64(sqrt(Float64(y + 1.0)) - Float64(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 (z <= 2.8e+14)
            		tmp = (sqrt((z + 1.0)) + 2.0) - (sqrt(z) + sqrt(y));
            	else
            		tmp = sqrt((x + 1.0)) + (sqrt((y + 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[z, 2.8e+14], N[(N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] + 2.0), $MachinePrecision] - N[(N[Sqrt[z], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] + N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[(N[Sqrt[y], $MachinePrecision] + N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \begin{array}{l}
            \mathbf{if}\;z \leq 2.8 \cdot 10^{+14}:\\
            \;\;\;\;\left(\sqrt{z + 1} + 2\right) - \left(\sqrt{z} + \sqrt{y}\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;\sqrt{x + 1} + \left(\sqrt{y + 1} - \left(\sqrt{y} + \sqrt{x}\right)\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if z < 2.8e14

              1. Initial program 96.3%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+96.3%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+96.3%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} \]
                4. +-commutative96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) \]
                5. associate-+r+96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right)} \]
                6. sub-neg96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} + \left(-\sqrt{t}\right)\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                7. sub-neg96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} - \sqrt{t}\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                8. +-commutative96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{\color{blue}{1 + t}} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
              3. Simplified62.3%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\left(\sqrt{1 + z} - \left(\sqrt{z} - \sqrt{1 + y}\right)\right) - \sqrt{y}\right)\right)} \]
              4. Taylor expanded in y around 0 52.1%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\color{blue}{\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right)} - \sqrt{y}\right)\right) \]
              5. Taylor expanded in x around 0 18.0%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \left(\sqrt{t} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              6. Step-by-step derivation
                1. associate-+r+18.0%

                  \[\leadsto \left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \color{blue}{\left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right)} \]
                2. +-commutative18.0%

                  \[\leadsto \left(2 + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + t}\right)}\right) - \left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right) \]
                3. +-commutative18.0%

                  \[\leadsto \left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \color{blue}{\left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              7. Simplified18.0%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              8. Taylor expanded in t around inf 33.1%

                \[\leadsto \color{blue}{\left(2 + \sqrt{1 + z}\right) - \left(\sqrt{y} + \sqrt{z}\right)} \]

              if 2.8e14 < z

              1. Initial program 86.7%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+86.7%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+86.7%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative86.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
                4. associate-+l+86.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
                5. +-commutative86.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
                6. associate-+l-47.6%

                  \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
              3. Simplified39.4%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
              4. Taylor expanded in t around inf 3.8%

                \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              5. Step-by-step derivation
                1. +-commutative3.8%

                  \[\leadsto \left(\sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + y}\right)}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right) \]
                2. associate--l+19.5%

                  \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + z} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right)} \]
                3. +-commutative19.5%

                  \[\leadsto \sqrt{1 + x} + \left(\color{blue}{\left(\sqrt{1 + y} + \sqrt{1 + z}\right)} - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right) \]
                4. +-commutative19.5%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \color{blue}{\left(\left(\sqrt{y} + \sqrt{z}\right) + \sqrt{x}\right)}\right) \]
                5. +-commutative19.5%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\color{blue}{\left(\sqrt{z} + \sqrt{y}\right)} + \sqrt{x}\right)\right) \]
              6. Simplified19.5%

                \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\left(\sqrt{z} + \sqrt{y}\right) + \sqrt{x}\right)\right)} \]
              7. Taylor expanded in z around inf 20.4%

                \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \sqrt{y}\right)} \]
              8. Step-by-step derivation
                1. associate--l+32.0%

                  \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\sqrt{1 + y} - \left(\sqrt{x} + \sqrt{y}\right)\right)} \]
                2. +-commutative32.0%

                  \[\leadsto \color{blue}{\left(\sqrt{1 + y} - \left(\sqrt{x} + \sqrt{y}\right)\right) + \sqrt{1 + x}} \]
                3. +-commutative32.0%

                  \[\leadsto \left(\sqrt{1 + y} - \color{blue}{\left(\sqrt{y} + \sqrt{x}\right)}\right) + \sqrt{1 + x} \]
              9. Simplified32.0%

                \[\leadsto \color{blue}{\left(\sqrt{1 + y} - \left(\sqrt{y} + \sqrt{x}\right)\right) + \sqrt{1 + x}} \]
            3. Recombined 2 regimes into one program.
            4. Final simplification32.5%

              \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq 2.8 \cdot 10^{+14}:\\ \;\;\;\;\left(\sqrt{z + 1} + 2\right) - \left(\sqrt{z} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\sqrt{x + 1} + \left(\sqrt{y + 1} - \left(\sqrt{y} + \sqrt{x}\right)\right)\\ \end{array} \]

            Alternative 14: 85.8% accurate, 2.0× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} \mathbf{if}\;z \leq 1.15 \cdot 10^{+14}:\\ \;\;\;\;\left(\sqrt{z + 1} + 2\right) - \left(\sqrt{z} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{x + 1} - \sqrt{x}\right)\\ \end{array} \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t)
             :precision binary64
             (if (<= z 1.15e+14)
               (- (+ (sqrt (+ z 1.0)) 2.0) (+ (sqrt z) (sqrt y)))
               (+ (- (sqrt (+ y 1.0)) (sqrt y)) (- (sqrt (+ x 1.0)) (sqrt x)))))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	double tmp;
            	if (z <= 1.15e+14) {
            		tmp = (sqrt((z + 1.0)) + 2.0) - (sqrt(z) + sqrt(y));
            	} else {
            		tmp = (sqrt((y + 1.0)) - sqrt(y)) + (sqrt((x + 1.0)) - sqrt(x));
            	}
            	return tmp;
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                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 <= 1.15d+14) then
                    tmp = (sqrt((z + 1.0d0)) + 2.0d0) - (sqrt(z) + sqrt(y))
                else
                    tmp = (sqrt((y + 1.0d0)) - sqrt(y)) + (sqrt((x + 1.0d0)) - 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 (z <= 1.15e+14) {
            		tmp = (Math.sqrt((z + 1.0)) + 2.0) - (Math.sqrt(z) + Math.sqrt(y));
            	} else {
            		tmp = (Math.sqrt((y + 1.0)) - Math.sqrt(y)) + (Math.sqrt((x + 1.0)) - Math.sqrt(x));
            	}
            	return tmp;
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	tmp = 0
            	if z <= 1.15e+14:
            		tmp = (math.sqrt((z + 1.0)) + 2.0) - (math.sqrt(z) + math.sqrt(y))
            	else:
            		tmp = (math.sqrt((y + 1.0)) - math.sqrt(y)) + (math.sqrt((x + 1.0)) - math.sqrt(x))
            	return tmp
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	tmp = 0.0
            	if (z <= 1.15e+14)
            		tmp = Float64(Float64(sqrt(Float64(z + 1.0)) + 2.0) - Float64(sqrt(z) + sqrt(y)));
            	else
            		tmp = Float64(Float64(sqrt(Float64(y + 1.0)) - sqrt(y)) + Float64(sqrt(Float64(x + 1.0)) - 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 (z <= 1.15e+14)
            		tmp = (sqrt((z + 1.0)) + 2.0) - (sqrt(z) + sqrt(y));
            	else
            		tmp = (sqrt((y + 1.0)) - sqrt(y)) + (sqrt((x + 1.0)) - 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[z, 1.15e+14], N[(N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] + 2.0), $MachinePrecision] - N[(N[Sqrt[z], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[y], $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \begin{array}{l}
            \mathbf{if}\;z \leq 1.15 \cdot 10^{+14}:\\
            \;\;\;\;\left(\sqrt{z + 1} + 2\right) - \left(\sqrt{z} + \sqrt{y}\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{x + 1} - \sqrt{x}\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if z < 1.15e14

              1. Initial program 96.3%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+96.3%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+96.3%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} \]
                4. +-commutative96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) \]
                5. associate-+r+96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right)} \]
                6. sub-neg96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} + \left(-\sqrt{t}\right)\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                7. sub-neg96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} - \sqrt{t}\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                8. +-commutative96.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{\color{blue}{1 + t}} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
              3. Simplified62.3%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\left(\sqrt{1 + z} - \left(\sqrt{z} - \sqrt{1 + y}\right)\right) - \sqrt{y}\right)\right)} \]
              4. Taylor expanded in y around 0 52.1%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\color{blue}{\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right)} - \sqrt{y}\right)\right) \]
              5. Taylor expanded in x around 0 18.0%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \left(\sqrt{t} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              6. Step-by-step derivation
                1. associate-+r+18.0%

                  \[\leadsto \left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \color{blue}{\left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right)} \]
                2. +-commutative18.0%

                  \[\leadsto \left(2 + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + t}\right)}\right) - \left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right) \]
                3. +-commutative18.0%

                  \[\leadsto \left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \color{blue}{\left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              7. Simplified18.0%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              8. Taylor expanded in t around inf 33.1%

                \[\leadsto \color{blue}{\left(2 + \sqrt{1 + z}\right) - \left(\sqrt{y} + \sqrt{z}\right)} \]

              if 1.15e14 < z

              1. Initial program 86.7%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+86.7%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+86.7%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative86.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
                4. associate-+l+86.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
                5. +-commutative86.7%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
                6. associate-+l-47.6%

                  \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
              3. Simplified39.4%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
              4. Taylor expanded in t around inf 3.8%

                \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              5. Step-by-step derivation
                1. +-commutative3.8%

                  \[\leadsto \left(\sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + y}\right)}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right) \]
                2. associate--l+19.5%

                  \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + z} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right)} \]
                3. +-commutative19.5%

                  \[\leadsto \sqrt{1 + x} + \left(\color{blue}{\left(\sqrt{1 + y} + \sqrt{1 + z}\right)} - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right) \]
                4. +-commutative19.5%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \color{blue}{\left(\left(\sqrt{y} + \sqrt{z}\right) + \sqrt{x}\right)}\right) \]
                5. +-commutative19.5%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\color{blue}{\left(\sqrt{z} + \sqrt{y}\right)} + \sqrt{x}\right)\right) \]
              6. Simplified19.5%

                \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\left(\sqrt{z} + \sqrt{y}\right) + \sqrt{x}\right)\right)} \]
              7. Step-by-step derivation
                1. +-commutative19.5%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\left(\sqrt{z} + \sqrt{y}\right) + \sqrt{x}\right)\right) + \sqrt{1 + x}} \]
                2. associate--r+19.2%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\sqrt{z} + \sqrt{y}\right)\right) - \sqrt{x}\right)} + \sqrt{1 + x} \]
                3. associate-+l-20.9%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\sqrt{z} + \sqrt{y}\right)\right) - \left(\sqrt{x} - \sqrt{1 + x}\right)} \]
                4. associate--r+14.9%

                  \[\leadsto \color{blue}{\left(\left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \sqrt{z}\right) - \sqrt{y}\right)} - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
                5. associate-+r-48.0%

                  \[\leadsto \left(\color{blue}{\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right)} - \sqrt{y}\right) - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
                6. +-commutative48.0%

                  \[\leadsto \left(\color{blue}{\left(\left(\sqrt{1 + z} - \sqrt{z}\right) + \sqrt{1 + y}\right)} - \sqrt{y}\right) - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
                7. associate-+l-14.9%

                  \[\leadsto \left(\color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{z} - \sqrt{1 + y}\right)\right)} - \sqrt{y}\right) - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
                8. associate--r+15.0%

                  \[\leadsto \color{blue}{\left(\sqrt{1 + z} - \left(\left(\sqrt{z} - \sqrt{1 + y}\right) + \sqrt{y}\right)\right)} - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
                9. +-commutative15.0%

                  \[\leadsto \left(\sqrt{1 + z} - \color{blue}{\left(\sqrt{y} + \left(\sqrt{z} - \sqrt{1 + y}\right)\right)}\right) - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
              8. Applied egg-rr15.0%

                \[\leadsto \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{y} + \left(\sqrt{z} - \sqrt{1 + y}\right)\right)\right) - \left(\sqrt{x} - \sqrt{1 + x}\right)} \]
              9. Taylor expanded in z around inf 48.0%

                \[\leadsto \color{blue}{\left(\sqrt{1 + y} - \sqrt{y}\right)} - \left(\sqrt{x} - \sqrt{1 + x}\right) \]
            3. Recombined 2 regimes into one program.
            4. Final simplification40.7%

              \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq 1.15 \cdot 10^{+14}:\\ \;\;\;\;\left(\sqrt{z + 1} + 2\right) - \left(\sqrt{z} + \sqrt{y}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{x + 1} - \sqrt{x}\right)\\ \end{array} \]

            Alternative 15: 82.0% accurate, 2.6× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} \mathbf{if}\;y \leq 1.6:\\ \;\;\;\;2 + \left(\sqrt{z + 1} - \left(\sqrt{z} + \sqrt{y}\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\sqrt{x + 1} - \sqrt{x}\\ \end{array} \end{array} \]
            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 1.6)
               (+ 2.0 (- (sqrt (+ z 1.0)) (+ (sqrt z) (sqrt y))))
               (- (sqrt (+ x 1.0)) (sqrt x))))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	double tmp;
            	if (y <= 1.6) {
            		tmp = 2.0 + (sqrt((z + 1.0)) - (sqrt(z) + sqrt(y)));
            	} else {
            		tmp = sqrt((x + 1.0)) - sqrt(x);
            	}
            	return tmp;
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                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 <= 1.6d0) then
                    tmp = 2.0d0 + (sqrt((z + 1.0d0)) - (sqrt(z) + sqrt(y)))
                else
                    tmp = sqrt((x + 1.0d0)) - 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 <= 1.6) {
            		tmp = 2.0 + (Math.sqrt((z + 1.0)) - (Math.sqrt(z) + Math.sqrt(y)));
            	} else {
            		tmp = Math.sqrt((x + 1.0)) - Math.sqrt(x);
            	}
            	return tmp;
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	tmp = 0
            	if y <= 1.6:
            		tmp = 2.0 + (math.sqrt((z + 1.0)) - (math.sqrt(z) + math.sqrt(y)))
            	else:
            		tmp = math.sqrt((x + 1.0)) - 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 <= 1.6)
            		tmp = Float64(2.0 + Float64(sqrt(Float64(z + 1.0)) - Float64(sqrt(z) + sqrt(y))));
            	else
            		tmp = Float64(sqrt(Float64(x + 1.0)) - 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 <= 1.6)
            		tmp = 2.0 + (sqrt((z + 1.0)) - (sqrt(z) + sqrt(y)));
            	else
            		tmp = sqrt((x + 1.0)) - 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, 1.6], N[(2.0 + N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] - N[(N[Sqrt[z], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Sqrt[N[(x + 1.0), $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 1.6:\\
            \;\;\;\;2 + \left(\sqrt{z + 1} - \left(\sqrt{z} + \sqrt{y}\right)\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;\sqrt{x + 1} - \sqrt{x}\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if y < 1.6000000000000001

              1. Initial program 97.3%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+97.3%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+97.3%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative97.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} \]
                4. +-commutative97.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) \]
                5. associate-+r+97.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right)} \]
                6. sub-neg97.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} + \left(-\sqrt{t}\right)\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                7. sub-neg97.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\sqrt{t + 1} - \sqrt{t}\right)} + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
                8. +-commutative97.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{\color{blue}{1 + t}} - \sqrt{t}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)\right) \]
              3. Simplified57.5%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\left(\sqrt{1 + z} - \left(\sqrt{z} - \sqrt{1 + y}\right)\right) - \sqrt{y}\right)\right)} \]
              4. Taylor expanded in y around 0 56.8%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{1 + t} - \sqrt{t}\right) + \left(\color{blue}{\left(\left(1 + \sqrt{1 + z}\right) - \sqrt{z}\right)} - \sqrt{y}\right)\right) \]
              5. Taylor expanded in x around 0 18.3%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \left(\sqrt{t} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              6. Step-by-step derivation
                1. associate-+r+18.3%

                  \[\leadsto \left(2 + \left(\sqrt{1 + t} + \sqrt{1 + z}\right)\right) - \color{blue}{\left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right)} \]
                2. +-commutative18.3%

                  \[\leadsto \left(2 + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + t}\right)}\right) - \left(\left(\sqrt{t} + \sqrt{y}\right) + \sqrt{z}\right) \]
                3. +-commutative18.3%

                  \[\leadsto \left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \color{blue}{\left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              7. Simplified18.3%

                \[\leadsto \color{blue}{\left(2 + \left(\sqrt{1 + z} + \sqrt{1 + t}\right)\right) - \left(\sqrt{z} + \left(\sqrt{t} + \sqrt{y}\right)\right)} \]
              8. Taylor expanded in t around inf 33.4%

                \[\leadsto \color{blue}{\left(2 + \sqrt{1 + z}\right) - \left(\sqrt{y} + \sqrt{z}\right)} \]
              9. Step-by-step derivation
                1. associate--l+59.3%

                  \[\leadsto \color{blue}{2 + \left(\sqrt{1 + z} - \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              10. Simplified59.3%

                \[\leadsto \color{blue}{2 + \left(\sqrt{1 + z} - \left(\sqrt{y} + \sqrt{z}\right)\right)} \]

              if 1.6000000000000001 < y

              1. Initial program 84.8%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+84.8%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+84.8%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative84.8%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
                4. associate-+l+84.8%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
                5. +-commutative84.8%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
                6. associate-+l-51.0%

                  \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
              3. Simplified21.1%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
              4. Taylor expanded in t around inf 3.9%

                \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              5. Step-by-step derivation
                1. +-commutative3.9%

                  \[\leadsto \left(\sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + y}\right)}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right) \]
                2. associate--l+20.7%

                  \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + z} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right)} \]
                3. +-commutative20.7%

                  \[\leadsto \sqrt{1 + x} + \left(\color{blue}{\left(\sqrt{1 + y} + \sqrt{1 + z}\right)} - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right) \]
                4. +-commutative20.7%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \color{blue}{\left(\left(\sqrt{y} + \sqrt{z}\right) + \sqrt{x}\right)}\right) \]
                5. +-commutative20.7%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\color{blue}{\left(\sqrt{z} + \sqrt{y}\right)} + \sqrt{x}\right)\right) \]
              6. Simplified20.7%

                \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\left(\sqrt{z} + \sqrt{y}\right) + \sqrt{x}\right)\right)} \]
              7. Taylor expanded in y around inf 26.2%

                \[\leadsto \sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{x} + \sqrt{z}\right)\right)} \]
              8. Step-by-step derivation
                1. +-commutative26.2%

                  \[\leadsto \sqrt{1 + x} + \left(\sqrt{1 + z} - \color{blue}{\left(\sqrt{z} + \sqrt{x}\right)}\right) \]
              9. Simplified26.2%

                \[\leadsto \sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{z} + \sqrt{x}\right)\right)} \]
              10. Taylor expanded in z around inf 20.2%

                \[\leadsto \color{blue}{\sqrt{1 + x} - \sqrt{x}} \]
            3. Recombined 2 regimes into one program.
            4. Final simplification41.0%

              \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq 1.6:\\ \;\;\;\;2 + \left(\sqrt{z + 1} - \left(\sqrt{z} + \sqrt{y}\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\sqrt{x + 1} - \sqrt{x}\\ \end{array} \]

            Alternative 16: 61.3% accurate, 3.9× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \begin{array}{l} t_1 := \sqrt{x + 1}\\ \mathbf{if}\;y \leq 2.8:\\ \;\;\;\;\left(t_1 + 1\right) - \sqrt{x}\\ \mathbf{else}:\\ \;\;\;\;t_1 - \sqrt{x}\\ \end{array} \end{array} \]
            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 (+ x 1.0))))
               (if (<= y 2.8) (- (+ t_1 1.0) (sqrt x)) (- t_1 (sqrt x)))))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	double t_1 = sqrt((x + 1.0));
            	double tmp;
            	if (y <= 2.8) {
            		tmp = (t_1 + 1.0) - sqrt(x);
            	} else {
            		tmp = t_1 - sqrt(x);
            	}
            	return tmp;
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                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((x + 1.0d0))
                if (y <= 2.8d0) then
                    tmp = (t_1 + 1.0d0) - sqrt(x)
                else
                    tmp = t_1 - 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((x + 1.0));
            	double tmp;
            	if (y <= 2.8) {
            		tmp = (t_1 + 1.0) - Math.sqrt(x);
            	} else {
            		tmp = t_1 - Math.sqrt(x);
            	}
            	return tmp;
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	t_1 = math.sqrt((x + 1.0))
            	tmp = 0
            	if y <= 2.8:
            		tmp = (t_1 + 1.0) - math.sqrt(x)
            	else:
            		tmp = t_1 - math.sqrt(x)
            	return tmp
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	t_1 = sqrt(Float64(x + 1.0))
            	tmp = 0.0
            	if (y <= 2.8)
            		tmp = Float64(Float64(t_1 + 1.0) - sqrt(x));
            	else
            		tmp = Float64(t_1 - 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((x + 1.0));
            	tmp = 0.0;
            	if (y <= 2.8)
            		tmp = (t_1 + 1.0) - sqrt(x);
            	else
            		tmp = t_1 - 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[(x + 1.0), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[y, 2.8], N[(N[(t$95$1 + 1.0), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], N[(t$95$1 - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]]]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \begin{array}{l}
            t_1 := \sqrt{x + 1}\\
            \mathbf{if}\;y \leq 2.8:\\
            \;\;\;\;\left(t_1 + 1\right) - \sqrt{x}\\
            
            \mathbf{else}:\\
            \;\;\;\;t_1 - \sqrt{x}\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if y < 2.7999999999999998

              1. Initial program 97.3%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+97.3%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+97.3%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative97.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
                4. associate-+l+97.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
                5. +-commutative97.3%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
                6. associate-+l-50.5%

                  \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
              3. Simplified50.5%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
              4. Taylor expanded in t around inf 17.8%

                \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              5. Step-by-step derivation
                1. +-commutative17.8%

                  \[\leadsto \left(\sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + y}\right)}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right) \]
                2. associate--l+21.5%

                  \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + z} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right)} \]
                3. +-commutative21.5%

                  \[\leadsto \sqrt{1 + x} + \left(\color{blue}{\left(\sqrt{1 + y} + \sqrt{1 + z}\right)} - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right) \]
                4. +-commutative21.5%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \color{blue}{\left(\left(\sqrt{y} + \sqrt{z}\right) + \sqrt{x}\right)}\right) \]
                5. +-commutative21.5%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\color{blue}{\left(\sqrt{z} + \sqrt{y}\right)} + \sqrt{x}\right)\right) \]
              6. Simplified21.5%

                \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\left(\sqrt{z} + \sqrt{y}\right) + \sqrt{x}\right)\right)} \]
              7. Taylor expanded in y around inf 11.3%

                \[\leadsto \sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{x} + \sqrt{z}\right)\right)} \]
              8. Step-by-step derivation
                1. +-commutative11.3%

                  \[\leadsto \sqrt{1 + x} + \left(\sqrt{1 + z} - \color{blue}{\left(\sqrt{z} + \sqrt{x}\right)}\right) \]
              9. Simplified11.3%

                \[\leadsto \sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{z} + \sqrt{x}\right)\right)} \]
              10. Taylor expanded in z around 0 23.7%

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

              if 2.7999999999999998 < y

              1. Initial program 84.8%

                \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
              2. Step-by-step derivation
                1. associate-+l+84.8%

                  \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
                2. associate-+l+84.8%

                  \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
                3. +-commutative84.8%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
                4. associate-+l+84.8%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
                5. +-commutative84.8%

                  \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
                6. associate-+l-51.0%

                  \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
              3. Simplified21.1%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
              4. Taylor expanded in t around inf 3.9%

                \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
              5. Step-by-step derivation
                1. +-commutative3.9%

                  \[\leadsto \left(\sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + y}\right)}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right) \]
                2. associate--l+20.7%

                  \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + z} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right)} \]
                3. +-commutative20.7%

                  \[\leadsto \sqrt{1 + x} + \left(\color{blue}{\left(\sqrt{1 + y} + \sqrt{1 + z}\right)} - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right) \]
                4. +-commutative20.7%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \color{blue}{\left(\left(\sqrt{y} + \sqrt{z}\right) + \sqrt{x}\right)}\right) \]
                5. +-commutative20.7%

                  \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\color{blue}{\left(\sqrt{z} + \sqrt{y}\right)} + \sqrt{x}\right)\right) \]
              6. Simplified20.7%

                \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\left(\sqrt{z} + \sqrt{y}\right) + \sqrt{x}\right)\right)} \]
              7. Taylor expanded in y around inf 26.2%

                \[\leadsto \sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{x} + \sqrt{z}\right)\right)} \]
              8. Step-by-step derivation
                1. +-commutative26.2%

                  \[\leadsto \sqrt{1 + x} + \left(\sqrt{1 + z} - \color{blue}{\left(\sqrt{z} + \sqrt{x}\right)}\right) \]
              9. Simplified26.2%

                \[\leadsto \sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{z} + \sqrt{x}\right)\right)} \]
              10. Taylor expanded in z around inf 20.2%

                \[\leadsto \color{blue}{\sqrt{1 + x} - \sqrt{x}} \]
            3. Recombined 2 regimes into one program.
            4. Final simplification22.1%

              \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq 2.8:\\ \;\;\;\;\left(\sqrt{x + 1} + 1\right) - \sqrt{x}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{x + 1} - \sqrt{x}\\ \end{array} \]

            Alternative 17: 35.4% accurate, 4.0× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ \sqrt{x + 1} - \sqrt{x} \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t) :precision binary64 (- (sqrt (+ x 1.0)) (sqrt x)))
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	return sqrt((x + 1.0)) - sqrt(x);
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                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)
            end function
            
            assert x < y && y < z && z < t;
            public static double code(double x, double y, double z, double t) {
            	return Math.sqrt((x + 1.0)) - Math.sqrt(x);
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	return math.sqrt((x + 1.0)) - math.sqrt(x)
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	return Float64(sqrt(Float64(x + 1.0)) - sqrt(x))
            end
            
            x, y, z, t = num2cell(sort([x, y, z, t])){:}
            function tmp = code(x, y, z, t)
            	tmp = sqrt((x + 1.0)) - sqrt(x);
            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[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            \sqrt{x + 1} - \sqrt{x}
            \end{array}
            
            Derivation
            1. Initial program 91.4%

              \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. Step-by-step derivation
              1. associate-+l+91.4%

                \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
              2. associate-+l+91.4%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
              3. +-commutative91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
              4. associate-+l+91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
              5. +-commutative91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
              6. associate-+l-50.8%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
            3. Simplified36.7%

              \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
            4. Taylor expanded in t around inf 11.3%

              \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
            5. Step-by-step derivation
              1. +-commutative11.3%

                \[\leadsto \left(\sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + y}\right)}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right) \]
              2. associate--l+21.1%

                \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + z} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right)} \]
              3. +-commutative21.1%

                \[\leadsto \sqrt{1 + x} + \left(\color{blue}{\left(\sqrt{1 + y} + \sqrt{1 + z}\right)} - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right) \]
              4. +-commutative21.1%

                \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \color{blue}{\left(\left(\sqrt{y} + \sqrt{z}\right) + \sqrt{x}\right)}\right) \]
              5. +-commutative21.1%

                \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\color{blue}{\left(\sqrt{z} + \sqrt{y}\right)} + \sqrt{x}\right)\right) \]
            6. Simplified21.1%

              \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\left(\sqrt{z} + \sqrt{y}\right) + \sqrt{x}\right)\right)} \]
            7. Taylor expanded in y around inf 18.3%

              \[\leadsto \sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{x} + \sqrt{z}\right)\right)} \]
            8. Step-by-step derivation
              1. +-commutative18.3%

                \[\leadsto \sqrt{1 + x} + \left(\sqrt{1 + z} - \color{blue}{\left(\sqrt{z} + \sqrt{x}\right)}\right) \]
            9. Simplified18.3%

              \[\leadsto \sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{z} + \sqrt{x}\right)\right)} \]
            10. Taylor expanded in z around inf 14.7%

              \[\leadsto \color{blue}{\sqrt{1 + x} - \sqrt{x}} \]
            11. Final simplification14.7%

              \[\leadsto \sqrt{x + 1} - \sqrt{x} \]

            Alternative 18: 34.3% accurate, 823.0× speedup?

            \[\begin{array}{l} [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\ \\ 1 \end{array} \]
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            (FPCore (x y z t) :precision binary64 1.0)
            assert(x < y && y < z && z < t);
            double code(double x, double y, double z, double t) {
            	return 1.0;
            }
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            real(8) function code(x, y, z, t)
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                real(8), intent (in) :: z
                real(8), intent (in) :: t
                code = 1.0d0
            end function
            
            assert x < y && y < z && z < t;
            public static double code(double x, double y, double z, double t) {
            	return 1.0;
            }
            
            [x, y, z, t] = sort([x, y, z, t])
            def code(x, y, z, t):
            	return 1.0
            
            x, y, z, t = sort([x, y, z, t])
            function code(x, y, z, t)
            	return 1.0
            end
            
            x, y, z, t = num2cell(sort([x, y, z, t])){:}
            function tmp = code(x, y, z, t)
            	tmp = 1.0;
            end
            
            NOTE: x, y, z, and t should be sorted in increasing order before calling this function.
            code[x_, y_, z_, t_] := 1.0
            
            \begin{array}{l}
            [x, y, z, t] = \mathsf{sort}([x, y, z, t])\\
            \\
            1
            \end{array}
            
            Derivation
            1. Initial program 91.4%

              \[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \]
            2. Step-by-step derivation
              1. associate-+l+91.4%

                \[\leadsto \color{blue}{\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)} \]
              2. associate-+l+91.4%

                \[\leadsto \color{blue}{\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\left(\sqrt{z + 1} - \sqrt{z}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right)\right)} \]
              3. +-commutative91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)}\right) \]
              4. associate-+l+91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \color{blue}{\left(\left(\left(\sqrt{y + 1} - \sqrt{y}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)} \]
              5. +-commutative91.4%

                \[\leadsto \left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\color{blue}{\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right)} + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) \]
              6. associate-+l-50.8%

                \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\left(\sqrt{t + 1} - \sqrt{t}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right)\right)} \]
            3. Simplified36.7%

              \[\leadsto \color{blue}{\sqrt{x + 1} - \left(\sqrt{x} - \left(\left(\sqrt{1 + y} + \left(\sqrt{1 + z} - \sqrt{z}\right)\right) - \left(\sqrt{y} - \left(\sqrt{1 + t} - \sqrt{t}\right)\right)\right)\right)} \]
            4. Taylor expanded in t around inf 11.3%

              \[\leadsto \color{blue}{\left(\sqrt{1 + x} + \left(\sqrt{1 + y} + \sqrt{1 + z}\right)\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)} \]
            5. Step-by-step derivation
              1. +-commutative11.3%

                \[\leadsto \left(\sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} + \sqrt{1 + y}\right)}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right) \]
              2. associate--l+21.1%

                \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + z} + \sqrt{1 + y}\right) - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right)} \]
              3. +-commutative21.1%

                \[\leadsto \sqrt{1 + x} + \left(\color{blue}{\left(\sqrt{1 + y} + \sqrt{1 + z}\right)} - \left(\sqrt{x} + \left(\sqrt{y} + \sqrt{z}\right)\right)\right) \]
              4. +-commutative21.1%

                \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \color{blue}{\left(\left(\sqrt{y} + \sqrt{z}\right) + \sqrt{x}\right)}\right) \]
              5. +-commutative21.1%

                \[\leadsto \sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\color{blue}{\left(\sqrt{z} + \sqrt{y}\right)} + \sqrt{x}\right)\right) \]
            6. Simplified21.1%

              \[\leadsto \color{blue}{\sqrt{1 + x} + \left(\left(\sqrt{1 + y} + \sqrt{1 + z}\right) - \left(\left(\sqrt{z} + \sqrt{y}\right) + \sqrt{x}\right)\right)} \]
            7. Taylor expanded in y around inf 18.3%

              \[\leadsto \sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{x} + \sqrt{z}\right)\right)} \]
            8. Step-by-step derivation
              1. +-commutative18.3%

                \[\leadsto \sqrt{1 + x} + \left(\sqrt{1 + z} - \color{blue}{\left(\sqrt{z} + \sqrt{x}\right)}\right) \]
            9. Simplified18.3%

              \[\leadsto \sqrt{1 + x} + \color{blue}{\left(\sqrt{1 + z} - \left(\sqrt{z} + \sqrt{x}\right)\right)} \]
            10. Taylor expanded in z around inf 14.7%

              \[\leadsto \color{blue}{\sqrt{1 + x} - \sqrt{x}} \]
            11. Taylor expanded in x around 0 37.1%

              \[\leadsto \color{blue}{1} \]
            12. Final simplification37.1%

              \[\leadsto 1 \]

            Developer target: 99.4% accurate, 1.0× speedup?

            \[\begin{array}{l} \\ \left(\left(\frac{1}{\sqrt{x + 1} + \sqrt{x}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right) \end{array} \]
            (FPCore (x y z t)
             :precision binary64
             (+
              (+
               (+
                (/ 1.0 (+ (sqrt (+ x 1.0)) (sqrt x)))
                (/ 1.0 (+ (sqrt (+ y 1.0)) (sqrt y))))
               (/ 1.0 (+ (sqrt (+ z 1.0)) (sqrt z))))
              (- (sqrt (+ t 1.0)) (sqrt t))))
            double code(double x, double y, double z, double t) {
            	return (((1.0 / (sqrt((x + 1.0)) + sqrt(x))) + (1.0 / (sqrt((y + 1.0)) + sqrt(y)))) + (1.0 / (sqrt((z + 1.0)) + sqrt(z)))) + (sqrt((t + 1.0)) - sqrt(t));
            }
            
            real(8) function code(x, y, z, t)
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                real(8), intent (in) :: z
                real(8), intent (in) :: t
                code = (((1.0d0 / (sqrt((x + 1.0d0)) + sqrt(x))) + (1.0d0 / (sqrt((y + 1.0d0)) + sqrt(y)))) + (1.0d0 / (sqrt((z + 1.0d0)) + sqrt(z)))) + (sqrt((t + 1.0d0)) - sqrt(t))
            end function
            
            public static double code(double x, double y, double z, double t) {
            	return (((1.0 / (Math.sqrt((x + 1.0)) + Math.sqrt(x))) + (1.0 / (Math.sqrt((y + 1.0)) + Math.sqrt(y)))) + (1.0 / (Math.sqrt((z + 1.0)) + Math.sqrt(z)))) + (Math.sqrt((t + 1.0)) - Math.sqrt(t));
            }
            
            def code(x, y, z, t):
            	return (((1.0 / (math.sqrt((x + 1.0)) + math.sqrt(x))) + (1.0 / (math.sqrt((y + 1.0)) + math.sqrt(y)))) + (1.0 / (math.sqrt((z + 1.0)) + math.sqrt(z)))) + (math.sqrt((t + 1.0)) - math.sqrt(t))
            
            function code(x, y, z, t)
            	return Float64(Float64(Float64(Float64(1.0 / Float64(sqrt(Float64(x + 1.0)) + sqrt(x))) + Float64(1.0 / Float64(sqrt(Float64(y + 1.0)) + sqrt(y)))) + Float64(1.0 / Float64(sqrt(Float64(z + 1.0)) + sqrt(z)))) + Float64(sqrt(Float64(t + 1.0)) - sqrt(t)))
            end
            
            function tmp = code(x, y, z, t)
            	tmp = (((1.0 / (sqrt((x + 1.0)) + sqrt(x))) + (1.0 / (sqrt((y + 1.0)) + sqrt(y)))) + (1.0 / (sqrt((z + 1.0)) + sqrt(z)))) + (sqrt((t + 1.0)) - sqrt(t));
            end
            
            code[x_, y_, z_, t_] := N[(N[(N[(N[(1.0 / N[(N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(N[Sqrt[N[(y + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(N[Sqrt[N[(z + 1.0), $MachinePrecision]], $MachinePrecision] + N[Sqrt[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[N[(t + 1.0), $MachinePrecision]], $MachinePrecision] - N[Sqrt[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \left(\left(\frac{1}{\sqrt{x + 1} + \sqrt{x}} + \frac{1}{\sqrt{y + 1} + \sqrt{y}}\right) + \frac{1}{\sqrt{z + 1} + \sqrt{z}}\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)
            \end{array}
            

            Reproduce

            ?
            herbie shell --seed 2023301 
            (FPCore (x y z t)
              :name "Main:z from "
              :precision binary64
            
              :herbie-target
              (+ (+ (+ (/ 1.0 (+ (sqrt (+ x 1.0)) (sqrt x))) (/ 1.0 (+ (sqrt (+ y 1.0)) (sqrt y)))) (/ 1.0 (+ (sqrt (+ z 1.0)) (sqrt z)))) (- (sqrt (+ t 1.0)) (sqrt t)))
            
              (+ (+ (+ (- (sqrt (+ x 1.0)) (sqrt x)) (- (sqrt (+ y 1.0)) (sqrt y))) (- (sqrt (+ z 1.0)) (sqrt z))) (- (sqrt (+ t 1.0)) (sqrt t))))