瞎模拟

#include<bits/stdc++.h>
using namespace std;
int nowprice,cun;
int a[13];
int main()
{
    for(int i=1;i<=12;i++)scanf("%d",&a[i]);
    for(int i=1;i<=12;i++)
    {
        int cost=a[i];
        nowprice+=300;
        nowprice-=cost;
        if(nowprice<0)
        {
            printf("-%d",i);return 0;
        }
        if(nowprice/100>0)
        {
            cun+=(nowprice/100)*100;
            nowprice-=(nowprice/100)*100;

        }
    }
    printf("%d",nowprice+cun*12/10);
    return 0;
}