#include <iostream>
#include <algorithm>
#include <vector>
#include<string>

using namespace std;
int main(){
	int n;
	cin >> n;
	vector<int> c(n);
	for (int i = 0; i < n; i++) cin >> c[i];
	
	int sum = 0;
	for (int i = 0; i < n; i++) sum += c[i];

	int ave = sum / n;
	int ans=0;
	for (int i = 0; i < n; i++) {
		if (ave >= c[i]) ans += 30;
	}
	cout << ans << endl;
}