include <bits/stdc++.h>

using namespace std; using T=pair<int,int>; int main() { int n,s,cnt=0; cin>>n>>s; vector <T> a(n); int d[n]; for (int i=0;i<n;i++) { cin>>a[i].first>>a[i].second; } for (int i=0;i<n;i++) { d[i]=a[i].second-a[i].first; } sort (d,d+n); for (int i=n-1;i>=0;i--) { //cout << d[i] << ' ' << s << '\n'; if (s + d[i]<0) break; s+=d[i]; cnt++; } cout<<cnt ; }