#include <bits/stdc++.h>
using namespace std;
int main() {
  int N, H;
  cin >> N >> H;
  int count = 0;
  vector<int> a(N + 1);
  vector<int> b(N + 1);
  for (int i = 1; i <= N; i++) {
    cin >> a.at(i) >> b.at(i);
  }
  sort(a.begin(), a.end(), greater<int>());
  sort(b.begin(), b.end(), greater<int>());
  for (int i = 0; i < N; i++) {
    if (b.at(i) > a.at(0)) {
      H -= b.at(i);
      count++;
      if (H < 0) {
        cout << count << endl;
        return 0;
      }
    } else {
      break;
    }
  }
  int sum_a = H / a.at(0);
  count += sum_a;
  cout << count << endl;
}
