错哪了啊喂

#include <iostream>
using namespace std;
int main()
{
    int a,b,sum=0,ikun;
    cin>>a>>b;
    for(int i=0;i<a;i++)
    {
        cin>>ikun;
        if(a-ikun<0)
        {
            sum++;
        }
        else
        {
            a-=ikun;
        }
    }
    cout <<sum;
    return 0;
}