#include <bits/stdc++.h>   using namespace std;   int n;   double P[1000];   int main() {     scanf( %d , &n);     for (int i = 0; i < n; i++) {       scanf( %lf , P + i);     }     sort(P, P + n);     reverse(P, P + n);     double x1 = 0;     double x2 = 1;     double res = 0;     for (int i = 0; i < n; i++) {       double s = (1 - P[i]);       if (s == 0) s = 1;       if (res == 1) break;       x1 += P[i] / s;       x2 *= s;       res = max(res, x1 * x2);     }     printf( %.12lf n , res);     return 0;   }   