Cannot sample enough valid points. (more)

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

1 + \sqrt{1 - \sqrt{1 + \sqrt{x}}}

double code(double x) {
	return ((double) (1.0 + ((double) sqrt(((double) (1.0 - ((double) sqrt(((double) (1.0 + ((double) sqrt(x))))))))))));
}

Reproduce

herbie shell --seed 2020153 
(FPCore (x)
  :name "(+ 1.0 (sqrt (- 1.0 (sqrt (+ 1.0 (sqrt x))))))"
  :precision binary64
  (+ 1.0 (sqrt (- 1.0 (sqrt (+ 1.0 (sqrt x)))))))