тернарный поиск

#include <iostream>
#include <string>
#include <cmath>

using namespace std;

int vp, vf;
double r = 1, l = 0;
double sep;
double eps;
double x;

double fun(double x)
{
	return ((sqrt(pow(1-sep, 2) + pow(x, 2)) / vp) + (sqrt(pow(sep, 2) + pow(1-x, 2)) / vf));
}

double tsearch(double l , double r, double eps)
{

	if ((r - l) < eps)
		return (l + r) / 2;
	double a = (2 * l + r) / 3;
	double b = (l + 2 * r) / 3;
	if (fun(b) > fun(a))
		return tsearch(l, b, eps);
	else
		return tsearch(a, r, eps);
}

int main()
{

	freopen("input.txt", "r", stdin);
	freopen("output.txt", "w", stdout);

	cin >> vp >> vf;
	cin >> sep;
	eps = pow(10, -12);

	printf("%.10lf\n", tsearch(l, r, eps));
	//cout << tsearch(l, r, eps);

}