#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, h, x;
  cin >> n >> h;
  vector<int> c(n);
  vector<int> d(n);
  bool y = true;
  for (int i = 0; i < n; i++) {
    cin >> c.at(i) >> d.at(i);
  }
  sort(c.begin(), c.end());
  reverse(c.begin(), c.end());
  sort(d.begin(), d.end());
  reverse(d.begin(), d.end());
  for (int i = 0; i < n; i++) {
    h -= d.at(i);
    if (h <= 0) {
      cout << i + 1 << endl;
      y = false;
      break;
    }
  }
  if (y) {
    x = h / c.at(0);
    if (h % c.at(0) > 0) {
      x++;
    }
    cout << x + n << endl;
  }
}
