#include<iostream>
#include<vector>
#include<algorithm>
#include<queue>
#include<iomanip>
using namespace std;

int main(){
    long long int n,h,k=0,ans=0;
    cin>>n>>h;
    vector<pair<long long int,long long int>>a(200000);
    vector<long long int>b(200000);
    for(long long int i=0;i<n;i++){
        cin>>a[i].first>>a[i].second;
        a[i].second*=-1;
    }
    sort(a.begin(),a.end(),greater<>());
    for(long long int i=0;i<n;i++){
        a[i].second*=-1;
    }
    for(long long int i=0;i<n;i++){
        if(a[0].first<a[i].second){
            b[k]=a[i].second;
            k++;
        }
    }
    sort(b.begin(),b.end(),greater<>());
    for(long long int i=0;;i++){
        if(i<k){
            h-=b[i];
            ans++;
        }
        else{
            ans+=h/a[0].first;
            break;
        }
        if(h<=0){
            break;
        }
    }
    cout<<ans<<endl;
    return 0;
}
