import java.util.*;
public class Main {
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int sum=0;
int cun=0;
for(int i=1;i<=12;i++) {
int ys=sc.nextInt();
int yl=sum+300;
if(yl<ys) {
System.out.println(-i);
System.exit(0);
}
if(yl-ys>100) {
sum=(yl-ys)%100;
cun=cun+(yl-ys)/100*100;
}
else
sum=yl-ys;
}
System.out.println((int)(sum+cun*1.2));
sc.close();
}
}
