#include <bits/stdc++.h>
using namespace std;
int main() {
  int N, h;
  cin >> N >> h;
  vector<int> vec(N);
  vector<int> vecb(N);
  for (int i = 0; i < N; i++) {
    cin >> vec.at(i);
    cin >> vecb.at(i);
  }
  sort(vec.begin(), vec.end());
  sort(vecb.begin(), vecb.end());
  int syamu = 0;
  for (int i = 0; i < N; i++) {
    if (vecb.at(N - 1 - i) > vec.at(N - 1)) {
      syamu += 1;
      h -= vecb.at(N - 1 - i);
    }
    if (h <= 0) {
      h = 0;
      break;
    }
  }
  int p;
  p = h / vec.at(N - 1);
  syamu += p;
  h = 0;
  cout << syamu << endl;
}
