简单的贪心
#include <iostream>
#include <algorithm>
using namespace std;
int n,s,a,b;
int yi[5000];
int main(){
cin>>n>>s>>a>>b;
int he=a+b;
int temp,tot=0,ans=0;
int ank=0;
for(int i=0,laji;i<n;++i){
cin>>temp;
if(temp<=he){
cin>>yi[ank];
ank++;
}
else{
cin>>laji;
continue;
}
}
sort(yi,yi+ank);
for(int i=0;i<ank;++i){
tot+=yi[i];
ans++;
//cout<<tot<<" "<<ans<<'\n';
if(tot>=s)break;
}
if(tot>s)ans-=1;
cout<<ans;
return 0;
}