func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int a;     int b;     cin >> a >> b;     cout.precision(13);     if (b > a) {       cout << -1;     } else if ((a % b == 0) && ((a / b) % 2 == 1)) {       cout << b;     } else {       int k = a / b;       if (k % 2 == 0) {         k--;       }       int dist = a - k * b;       double x1 = b;       double x2 = (double)dist / (double)k + (double)b;       double x = x1;       double ang;       double x_old;       for (int i = 0; i < 50; i++) {         ang = (x - b) / (k * x - a);         x_old = x;         if (ang > -1) {           x = (x + x2) / 2.0;           x1 = x_old;         } else if (ang < -1) {           x = (x + x1) / 2.0;           x2 = x_old;         } else {           cout << x;           return 0;         }       }       cout << x;     }     return 0;   }   