_```cpp
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cstring>
#include<iostream>
#include<cmath>
using namespace std;
int cnt=0;
struct point{
int x,y;
point(int x=0,int y=0):x(x),y(y){}
};
bool operator < (const point &e,const point &w){
if(e.y>w.y) return false;
return true;
}
point g[10000000];
int main(){
int q,s;
int b,i;
scanf("%d %d",&q,&s);
scanf("%d %d",&b,&i);
int a=b+i;
for(int r=0;r<q;r++){
scanf("%d %d",&g[r].x,&g[r].y);
}
sort(g,g+q);
for(int p=0;p<q;p++){
if(a>=g[p].x) cnt++,s=s-g[p].y;
if(s<0) {
cnt--;
break;
}
}
printf("%d",cnt);
}
```_
by wzm_ @ 2019-01-18 11:19:52