#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];
int n,y;
using namespace std;
int main(){
  int num=0;
  cin>>n>>y;
  for (int i=0;i<n;i++)
  cin>>a[i]>>b[i];
  sort (a,a+n);
  int sub=a[0];
  sort (b,b+n);
  for (int  i=0;i<n;i++)
  if ((b[i] > sub) and (y > 0)){
  h -= b[i];
  num++;
  }
  if (y > 0) 
  num += (h + sub - 1) / sub;
  cout<<num;
  system ("pause");
  return 0;
  }