#include <bits/stdc++.h>
#define pb push_back
#define fst first
#define snd second
#define all(c) c.begin(),c.end()
using namespace std;
typedef long long ll;
const ll INF64 = 1e18 + 1337;
const int INF32 = 1e9 + 228;
const int MOD = 1e9 + 7;
int main()
{
    ios_base::sync_with_stdio(0);
#ifndef __WIN32
    ifstream cin("input.txt");
    ofstream cout("output.txt");
#endif
    cin.tie(0);cout.tie(0);

    ll n, _t;
    cin >> n >> _t;
    multiset<ll> s;
    ll sum = 0;
    ll ans = 0;
    for(int i = 0; i < n; i++)
    {
        ll x, t;
        cin >> x >> t;
        while(sum + x > _t)
        {
            auto it = prev(s.end());
            sum -= *it;
            s.erase(it);
        }
        if(sum + x + t <= _t)
        {
            s.insert(t);
            sum += t;
        }
        ans = max(ans, (ll)s.size());
    }
    cout << ans;



#ifndef __WIN32
  cin.close();
  cout.close();
#endif
    return 0;
}