#include <iostream>
#include <string>
#include <algorithm>
using namespace std;
int main(void){
    int n,h,a[200002];
    cin>>n>>h;
    for(int i=0;i<n;i++){
        cin>>a[i]>>a[i+n];
    }
    sort(a,a+n);
    sort(a+n,a+2*n);
    int m=a[n-1];
    int ans=0,k=0;
    while(h>0){
        if(a[2*n-1-k]>m){
            h-=a[2*n-1-k];
            ans++;
            k++;
        }else{
            h-=m;
            ans++;
        }
    }
    cout<<ans;
    return 0;
}
