// #define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
int main() {
    // Input
    int N;
    cin >> N;
    vector<int> C(N);
    rep(i, N) cin >> C[i];

    // Judge
    int ans = 0;
    int votes = accumulate(C.begin(), C.end(), 0);
    rep(i, N) if (C[i] * 10 <= votes) ++ans;

    // Output
    cout << 30 * ans << endl;
}