啊这，20行的事，正解

#include<bits/stdc++.h>
using namespace std;
int main(){
int a,qian=0,mama=0,ke=0,e;
for(int i=1;i<=12;i++){
cin>>a;
qian+=300;
qian-=a;
if(qian<0){
cout<<"-"<<i;
return 0;
}else{
mama+=qian/100;
qian%=100;
}
}
qian+=mama*120;
cout<<qian;
return 0;
}