#include<bits/stdc++.h>
#define f(i,n) for(int i=0;i<n;i++)
#define F first
#define S second
#define mod 1000000007
#define P pair<int,int>
using namespace std;
int x[100000],y[100000];
signed main(){
	int a,b,ans=0;
	cin>>a>>b;
	f(i,a){
		cin>>x[i]>>y[i];
	}
	sort(x,x+a);
	sort(y,y+a);
	auto Itr=upper_bound(y,y+a,x[a-1])-y;
	for(int i=a-1;i>=Itr;i--){
		ans++;
		b-=y[i];
		if(b<=0){
			cout<<ans<<endl;
			return 0;
		}
	}
	cout<<ans+(b-1)/x[a-1]+1<<endl;
}
