有人看看为什么有两个测试点是re吗 只有60分

#include<iostream>
#include<algorithm>
using namespace std;
struct apple
{
    int x,y;
}app[5005];
bool cmp(apple app1,apple app2)
{
    return app1.y<=app2.y;
}
int main()
{
    int n,s,a,b,ans=0;
    cin>>n>>s>>a>>b;
    for(int i=1;i<=n;i++)
    cin>>app[i].x>>app[i].y;
    sort(app+1,app+n+1,cmp);
    for(int i=1;i<=n;i++)
    {
        if(s>=app[i].y)
        {
            if(app[i].x<=b || app[i].x<=b+a)
            {
                ans++;
                s=s-app[i].y;
                if(s<=0)
                break;
            }
        }
    }
    cout<<ans<<endl;
    return 0;
}