#include <bits/stdc++.h>
using namespace std;
int main(int argc, const char* argv[]) {
  int n, h;
  cin >> n >> h;
  int a[n], b[n];
  for (int i = 0; i < (n); i++) {
    cin >> a[i] >> b[i];
  }
  sort(a, a + n);
  sort(b, b + n);
  int cnt = 0;
  int pt = -1;
  for (int i = 0; i < (n); i++) {
    if (a[n - 1] > b[i]) {
      pt = i;
    } else {
      break;
    }
  }
  for (int i = n - 1; i > pt; i--) {
    h -= b[i];
    cnt++;
    if (h <= 0) {
      cout << cnt << endl;
      return 0;
    }
  }
  cnt += h / a[n - 1];
  cout << cnt << endl;
  return 0;
}
