func_code_string: #include <bits/stdc++.h>   using namespace std;   const int nn = 115;   const double PI = 2 * acos(0);   int main() {     int n;     double r;     double ans;     cin >> n >> r;     double x = (PI * (180 - (360.0 / n)) / 2.0) / 180.0;     double L = 0, R = 1e5;     while (L <= R) {       double mid = (L + R) / 2.0;       if (fabs(cos(x) * (mid + r) - mid) < 1e-9) {         ans = mid;         break;       } else if (cos(x) * (mid + r) > (mid)) {         L = mid;       } else {         R = mid;       }     }     printf( %.6f n , ans);   }   