为什么我第二个数据输出1583

#include<cstdio>
#include<iostream>
using namespace std;
int a[13];
int sum=0;int ans;
int main()
{
    for(int i=1;i<=12;i++)
    {
        scanf("%d",&a[i]);
        if(a[i]>300)
        {
            if(sum>=a[i]-300)
            {
                sum-=a[i]-300;
                if(sum>=100)
                {
                    int oo=sum/100;
                    sum-=oo*100;
                    ans+=oo*100;
                } 
                continue;
            }
            else
            {
                //printf("-");
                printf("%d",-i);
                return 0;
            }
        }
        else
        {
            if(sum+300-a[i]>=100)
            {
                sum+=300-a[i];
                int pp=sum/100;
                sum-=pp*100;
                ans+=pp*100;
            }
            else
                sum+=300-a[i];
            continue;
        }
    }
    ans+=sum;
    ans=ans*1.2;
    cout<<ans;
    return 0;
}
望大佬解答，谢谢