#include <bits/stdc++.h>
using namespace std;
using ll = long long;
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());
  sort(b.begin(), b.end());
  reverse(b.begin(), b.end());
  int cnt = 0;
  while (h > 0 && b[cnt] >= a[n - 1]) {
    h -= b[cnt];
    cnt++;
  }
  cnt += h / a[n - 1];
  cout << cnt << endl;
}
