#include<iostream>
#include<algorithm>
#include<vector>

using namespace std;

int main()
{
	int n,h;
	cin >> n >> h; 
	
	vector<int> a(n),b(n);
	for(int i=0;i<n;i++)
		cin >> a[i] >> b[i];
	
	sort(a.begin(),a.end(),greater<int>());
	sort(b.begin(),b.end(),greater<int>());

	int count=0;

	for(int i=0;i<n;i++)
	{
		if(b[i]<a[0])break;
		count++;
		h-=b[i];
		if(h<=0)
		{
			cout << count << endl;
			return 0;
		}
	}

	count+=((h-1)/a[0]+1);

	cout<< count << endl;
}

