#include<bits/stdc++.h>
using namespace std;

struct node {
    int h;
    int w;
}apple[5010];

int n, s, a, b, num;

bool cmp(node x, node y) {
    return x.w < y.w;
}

int main() {
    scanf("%d%d", &n, &s);
    for (int i = 1; i <= n; i++) {
    	scanf("%d", &apple[i].h);
    	scanf("%d", &apple[i].w);
	}
	sort(apple+1, apple+1+n, cmp);
	for (int i = 1; i <= n; i++) {
    	if (a + b >= apple[i].h && s >= apple[i].w) {
    	    s-=apple[i].w;
    	    num+=1;
    	}
	}
	printf("%d", num);
}