```cpp
#include<iostream>
using namespace std;
int xi[5001],yi[5001];
int main()
{
int n,s,a,b,app=0;
cin>>n>>s>>a>>b;
a+=b;
for(int i=0;i<n;i++) cin>>xi[i]>>yi[i];
for(int i=0;i<n;i++)
{
for(int j=i+1;j<n;j++)
{
if(yi[j]<yi[i])
{
swap(xi[j],xi[i]);
swap(yi[j],yi[i]);
}
}
}
for(int i=0;i<n;i++)
{
if(s<=0) break;
if(xi[i]<=a&&s-yi[i]>=0)
{
app++;
s-=yi[i];
}
}
cout<<app;
return 0;
}
```
by Administrator2004 @ 2017-07-17 22:35:09
@[Administrator2004](/space/show?uid=41421) 谢谢哈！
by 5u0i5n11i @ 2017-07-18 15:12:50
@[superhandsomejack](/space/show?uid=47994) 不用谢
by Administrator2004 @ 2017-07-18 20:59:30