func_code_string: #include <bits/stdc++.h>   using namespace std;   const int MAXN = 55;   int n, m;   int a[MAXN];   double dp[MAXN][MAXN][MAXN];   double C[MAXN][MAXN];   void init() {     C[0][0] = 1.0;     for (int i = 1; i <= 50; i++) {       C[i][0] = 1.0;       for (int j = 1; j <= i; j++) C[i][j] = C[i - 1][j - 1] + C[i - 1][j];     }   }   int main() {     scanf( %d%d , &n, &m);     init();     for (int i = 1; i <= m; i++) scanf( %d , &a[i]);     for (int i = 0; i <= n; i++) dp[0][0][i] = i;     for (int i = 1; i <= m; i++) {       for (int j = 0; j <= n; j++) {         for (int k = 0; k <= n; k++) {           for (int c = 0; c <= j; c++) {             int maxq = max(k, (c + a[i] - 1) / a[i]);             dp[i][j][k] +=                 dp[i - 1][j - c][maxq] * pow(i - 1, j - c) / pow(i, j) * C[j][c];           }         }       }     }     printf( %.12f n , dp[m][n][0]);     return 0;   }   