#include <bits/stdc++.h>
using namespace std;
int main() {
  int N, H, a[100000], b[100000];
  cin >> N >> H;
  for (int i = 0; i < N; ++i) {
    cin >> a[i] >> b[i];
  }
  sort(a, a + N);
  sort(b, b + N);
  for (int i = 0; i < N; ++i) {
    if (b[N - i - 1] > a[N - 1]) {
      H -= b[N - i - 1];
    } else {
      i += ceil(H / a[N - 1]);
      cout << i << endl;
      return 0;
    }
    if (H <= 0) {
      cout << i << endl;
    }
  }
  return 0;
}
