#include <bits/stdc++.h>
using namespace std;
using namespace std;
int main(void) {
  int n, h;
  int a, b;
  int res = 2000000000;
  int wield = 0;
  vector<int> v;
  scanf("%d %d", &n, &h);
  for (int i = 0; i < n; i++) {
    scanf("%d %d", &a, &b);
    wield = max(wield, a);
    v.push_back(b);
  }
  sort(v.rbegin(), v.rend());
  for (int i = 0; i < v.size(); i++) {
    int count = (i + 1);
    a = v[i];
    h -= a;
    int c = ceil((h * 1.0) / wield);
    count += c;
    res = min(res, count);
    if (h < 0) {
      break;
    }
  }
  cout << res << '\n';
  return 0;
}
