#include <bits/stdc++.h>
using namespace std;
int main(void) {
  int n, h;
  scanf("%d %d", &n, &h);
  vector<pair<int, int>> v(n);
  for (int i = 0; i < n; ++i) {
    scanf("%d %d", &v[i].first, &v[i].second);
  }
  sort(v.rbegin(), v.rend());
  pair<int, int> val1 = v[0];
  v[0].first = v[0].second = -1;
  for (int i = 0; i < n; ++i) {
    swap(v[i].first, v[i].second);
  }
  sort(v.rbegin(), v.rend());
  int c = 0;
  for (int i = 0; i < n - 1 && v[i].first >= val1.first && h > 0;
       ++i, ++c, h -= v[i - 1].first)
    ;
  while (h > 0) {
    if (h - val1.second > 0) {
      c++;
      h -= val1.first;
    } else
      c++, h -= val1.second;
  }
  printf("%d\n", c);
}
