#include <bits/stdc++.h>
using namespace std;
int main(void) {
  int n, h;
  cin >> n >> h;
  vector<pair<int, int>> k1(n), k2(n);
  for (int i = 0; i < n; i++) {
    int a, b;
    cin >> a >> b;
    k1[i] = {a, b};
    k2[i] = {b, a};
  }
  sort(k1.begin(), k1.end());
  reverse(k1.begin(), k1.end());
  int saitsuyo = k1[0].first;
  int ans = h / saitsuyo + 1;
  sort(k2.begin(), k2.end());
  vector<int> nage;
  for (int i = 0; i < n; i++) {
    if (saitsuyo < k2[i].first) nage.push_back(k2[i].first);
  }
  int cnt = 0;
  for (int i = 0; i < nage.size(); i++) {
    h -= nage[i];
    cnt++;
  }
  if (h <= 0) {
    cout << nage.size() << endl;
    return 0;
  }
  ans = min(ans, cnt + h / saitsuyo + bool(h % saitsuyo));
  cout << ans << endl;
}
