#include<iostream>
using namespace std;
int main(){
    int rep = 0, cost, budget, bank, surplus = 0, deposit;
    for(int i = 1; i <= 12; i++){
        rep = surplus + 300;
        surplus = 0;
        cin >> cost;
        budget = rep - cost;
        if(budget < 0){
            cout << -i;
            return 0;
        }
        if(budget >= 100){
            deposit = budget / 100 * 100;
            bank += deposit;
            surplus = budget - deposit;
        }else{surplus += budget;}
    }
    cout << surplus + bank * 1.2;
    return 0;
}