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

int main(){
  int n,m;
  cin>>n>>m;
  int dmax=2e6;
  vector<int> d(n),c(dmax+1);
  for (int i=0;i<n;i++){
    int a,b;
    cin>>a>>b;
    d[i]=min(dmax,(m-a)/b);
    c[d[i]]++;
  }
  int ans=0;
  int now=0;
  for (int i=0;i<=dmax;i++){
    now+=c[i];
    ans=max(ans,(now+i)/(i+1));
  }
  cout<<ans<<endl;
}