#include <algorithm>
#include <cstdio>
#include <iostream>
#include <cfloat>
#include <climits>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <queue>
#include <sstream>
#include <stack>
#include <time.h>
#include <vector>
#include <complex>
int a[10004];
int b[10005];
using namespace std;
int main(){
  int n,y,mx=0,ans=0;
  cin>>n>>y;
  for (int i=0;i<n;i++)
  cin>>a[i]>>b[i];
  sort (a,a+n);
  mx=a[n-1];
  for (int j=0;j<n;j++)
  if (y <= 0){
  cout<<ans;
  system ("pause");
  return 0;
  }
  if (b[j] >= mx){
  y -= b[j];
  ans++;
  }
  if (y > 0)
  ans += (y + mx - 1) / mx;
  cout<<ans;
  system ("pause");
  return 0;
  }