func_code_string: #include <bits/stdc++.h>   using namespace std;   const double PI = acos(-1.0);   const double eps = 1e-11;   const int INF = 101e7;   template <class T>   T sqr(T first) {     return first * first;   }   template <class T>   T abs(T first) {     return (first < 0) ? -first : first;   }   int main() {     int n, m, h;     cin >> n >> m >> h;     n--;     int sh = 0, sum = 0;     for (int _b = (m), i = (1); i <= _b; i++) {       if (i == h) {         cin >> sh;         sh--;       } else {         int k;         cin >> k;         sum += k;       }     }     if (n > sh + sum) {       cout <<  -1 n ;       return 0;     }     double c = 1;     for (int i = 0, _n = (n); i < _n; i++) {       c *= (double(sum) / (sum + sh));       sum--;     }     printf( %.8f n , 1 - c);     return 0;   }   