dalao救助!只有倒数第二个测试点对了

#include<bits/stdc++.h>
using namespace std;
int main(){
    int n,s,a,b,ans=0,sum;
    cin>>n>>s;
    cin>>a>>b; 
    sum=s;
    int x[n],y[n];
    for(int i=1;i<=n;i++)
     cin>>x[i]>>y[i];
    for(int i=1;i<=n;i++)
     if(a+n+b>=x[i]&&sum-y[i]>=0)
      ans++,sum-=y[i];
    cout<<ans;
    return 0;
}