#include<bits/stdc++.h>
using namespace std;

int qian, cui, kaizhi;
int main(){
	int a[13];
	for (int i = 1; i <= 12; i++) cin >> a[i];
	for (int i = 1; i <= 12; i++){
		qian+=300;
		if (qian < a[i]) {
			printf("-%d", i);
			return 0;
		}
		qian -= a[i];
		cui += qian/100;
		qian %= 100;
	}
	double x = qian+cui*1.2;
	cout << x;
}