津津的储蓄计划

#include<iostream>
using namespace std;
int main()
{int n;
int sum=0;
int s=0;
int yu;
int y;
for(int i=1;i<=12;i++)
{
s+=300;
cin>>n;
yu=s-n;
if(yu<0)
{cout<<"-"<<i;break;}
if(yu/100!=0)
{sum=sum+(yu/100)*100;
yu=yu-(yu/100)*100;
}
s=yu;
if(i==12)
{
y=s+sum+(sum/10)*2;
cout<<y;
}
}
return 0;
}