#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int n,m;
struct room{
    ll pos;
    int t;
}a[100005];
ll ans,akcnt,tim;
priority_queue<ll> q;
bool cmp(room aa,room bb){
    return aa.pos<bb.pos;
}
int main()
{
    scanf("%d%d",&n,&m);
    for(int i=1;i<=n;i++){
        scanf("%lld%d",&a[i].pos,&a[i].t);
    }
    sort(a+1,a+n+1,cmp);
    for(int i=1;i<=n;i++){
        akcnt++;
        tim+=a[i].pos-a[i-1].pos;
        tim+=a[i].t;
        q.push(a[i].t);
        while(tim>m&&!q.empty()){
            akcnt--;
            tim-=q.top();
            q.pop();
        }
        if(tim>m) break;
        ans=max(akcnt,ans);
    }
    printf("%lld\n",ans);

    return 0;
}