Use the --timeout flag to change the timeout.
\frac{-\left(f + n\right)}{f - n}double f(double f, double n) {
double r81796 = f;
double r81797 = n;
double r81798 = r81796 + r81797;
double r81799 = -r81798;
double r81800 = r81796 - r81797;
double r81801 = r81799 / r81800;
return r81801;
}
herbie shell --seed 2019235
(FPCore (f n)
:name "subtraction fraction"
:precision binary64
(/ (- (+ f n)) (- f n)))