#include<bits/stdc++.h>
using namespace std;
priority_queue<long long,vector<long long>,greater<long long> >p;
priority_queue<long long,vector<long long>,greater<long long> >ti;
priority_queue<long long,vector<long long>,less<long long> >ch;
long long tim,pos[100005],t[100005],ma,dis,num,ans,n;
signed main()
{
	cin>>n>>tim;
	for(long long i=1;i<=n;i++)
	{
		long long m1,m2;
		cin>>m1>>m2;
		p.push(m1);
		ti.push(m2);
	}
	for(long long i=1;i<=n;i++)
	{
		pos[i]=p.top();
		p.pop();
		t[i]=ti.top();
		ti.pop();
	}
	for(long long i=1;i<=n;i++)
	{
		if(ch.empty())
		{
			ma=-1;
		}
		else ma=ch.top();
		while(tim<dis and !ch.empty())
		{
			tim+=ch.top();
			num--;
			ch.pop();
		}
		if(tim<dis)break;
		tim-=dis;
		if(ma>t[i])
		{
			while(tim<t[i] and !ch.empty())
			{
				tim+=ch.top();
				num--;
				ch.pop();
			}
		}
		if(tim>t[i] and (ma==-1 or ma>t[i]))
		{
			tim-=t[i];
			num++;
			if(num>ans)ans=num;
		}
		dis=pos[i+1]-pos[i];
	}
	cout<<ans;
	return 0;
}