fork download
copy 
  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. int n;
  4. long double p[3005];
  5. long double dp[3005][3005];
  6.  
  7. main() {
  8.     ios_base::sync_with_stdio(false);
  9.     cin.tie(0); cout.tie(0);
  10.     freopen("TEST.inp", "r", stdin);
  11.     freopen("TEST.out", "w", stdout);
  12.     cin >> n;
  13.     for (int i = 1; i <= n; i++) cin >> p[i];
  14.  
  15.     dp[1][0] = 1 - p[1];
  16.     dp[1][1] = p[1];
  17.     for (int i = 2; i <= n; i++) {
  18.         for (int j = 0; j <= i; j++) {
  19.             dp[i][j] += dp[i - 1][j - 1] * p[i] + dp[i - 1][j] * (1 - p[i]);
  20.         }
  21.     }
  22.     long double ans = 0;
  23.     for (int i = n / 2 + 1; i <= n; i++) ans += dp[n][i];
  24.  
  25.     cout << fixed << setprecision(9) << ans << '\n';
  26.  
  27.     return 0;
  28. }
  29.  
Success #stdin #stdout 0.01s 5284KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
Standard output is empty
https://ideone.com/rNtiJO
language:
C++14 (gcc 8.3)
created:
7 hours ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!