тернарный поиск

#include <iostream>
#include <cmath>
#include <iomanip>

using namespace std;

double function (double v1, double v2, double a, double x)
{
  double time;
  time = (sqrt((1-a)*(1-a) + x*x))/v1 + (sqrt((1-x)*(1-x) + a*a))/v2;
  return time;
}

double poisk (double v1, double v2, double a, double left, double right)
{
 double m1, m2;
  while (right - left > 0.00000001)
  {
     m1 = left + (right - left)/3;
     m2 = right - (right - left)/3;

    double znach1 = function (v1, v2, a, m1);
    double znach2 = function (v1, v2, a, m2);
    //cout << znach1 << " " << znach2 << endl;
    if (znach1 > znach2)
     left = m1;
    else if (znach1 < znach2)
     right = m2;
     else if (znach1 == znach2)
      {
        left = m1;
        right = m2;
      }
  }
  //cout << m1 << " ";
  return left;
}

int main ()
{
  double speed_1, speed_2, granica;

  cin >> speed_1 >> speed_2;
  cin >> granica;

  cout.setf(ios::fixed);  // вывод в фиксированном формате
  cout.precision(8);

  cout << poisk (speed_1, speed_2, granica, 0, 1);
}