#include<iostream>
#include<string>
#include<algorithm>
#include<vector>
#include<iomanip>
#include<math.h>
#include<complex>
#include<queue>
#include<deque>
#include<stack>
#include<map>
#include<set>
#include<bitset>
using namespace std;
#define REP(i,m,n) for(int i=(int)m ; i < (int) n ; ++i )
#define rep(i,n) REP(i,0,n)
typedef long long ll;
typedef pair<int,int> pint;
typedef pair<ll,int> pli;
const int inf=1e9+7;
const ll longinf=1LL<<60 ;
const ll mod=1e9+7 ;
    using namespace std;
 
int GCD(int a, int b) {
    if (b == 0) return a;
    else return GCD(b, a % b);
}
 
    int main(){
      ll n,h;
      cin >> n >> h;
      ll a[n],b[n];
      rep(i,n){
       cin >> a[i] >> b[i]; 
      }
      sort(a,a+n);
      reverse(a,a+n);
      sort(b,b+n);
      reverse(b,b+n);
      ll ans=0;
       rep(i,n){
        if(b[i]>=a[n-1] && h>0){
         h-=b[i];
          ans++;
        }
       }
      while(h>0){
       h-=a[n-1];
        ans++;
      }
      cout << ans << endl;
      return 0;}
