#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int main() {
	int N, num = 0; cin >> N;
	vector<long long> C(N);
	long long M = 0;
	for (int i = 0; i < N;i++) {
		cin >> C[i];
		M += C[i];
	}
	M /= 10;
	sort(C.begin(), C.end());
	for (int i = 0; i < N;i++) {
		if (M >= C[i]) { num++; continue; }
		else {
			break;
		}
	}
	cout << 30 * num << endl;
	return 0;
}