#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, h;
  cin >> n >> h;
  vector<int> a;
  vector<int> b;
  for (int i = 0; i < (n); i++) {
    int tmpa, tmpb;
    cin >> tmpa >> tmpb;
    a.push_back(tmpa);
    b.push_back(tmpb);
  }
  sort((a).begin(), (a).end());
  sort((b).begin(), (b).end());
  int maxa = a[n - 1];
  int ans = ((h + (maxa - 1)) / maxa);
  int tmph = h;
  for (int i = 0; i < (n); i++) {
    tmph -= b[n - 1 - i];
    if (tmph >= 0) ans = min(ans, (i + 1) + ((tmph + (maxa - 1)) / maxa));
  }
  cout << ans << endl;
  return 0;
}
