#include <bits/stdc++.h>

using namespace std;

int Left, save;

int main() {
    for (int i = 1; i <= 12; i++) {
        Left += 300;
        int x;
        cin >> x;
        Left = Left - x;
        if (Left < 0) {
            printf("-%d", i);
            exit(0);
        }
        int cnt = Left / 100;
        save += (100 * cnt);
        Left -= (100 * cnt);
    }
    printf("%d", (int)(1.2 * save) + Left);
    return 0;
}