Submission #1624056

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Source Code Expand

#include <bits/stdc++.h>
#define mem(a,b) memset(a,b,sizeof(a))
#define REP(i,n) for (int i=0;i<(n);i++)
#define FOR(i,s,e) for (int i=s;i<(e);i++)
using namespace std;
typedef long long llint;
typedef pair<int, int> P;
const int MOD = (int)1e9 + 7;
const int INF = 999999999;
const double PI = acos(-1.0);

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);

    int N;
    cin >> N;
    int C[100];
    double ans;
    REP(i, N){
        cin >> C[i];
    }
    REP(i, N){
        int S = 0;
        REP(j, N){
            if(C[i] > C[j] && C[i]%C[j] == 0) S++;
        }
        if(S%2 == 1) ans += 1/2.0;
        else ans += (S+2.0)/(2.0*S+2.0);
    }

    cout << setprecision(12) << ans << "\n";
    return 0;
}

Submission Info

Judge Result