#include <bits/stdc++.h>
using namespace std;
bool custom(pair<int, int> a, pair<int, int> b) {
  if (a.first == b.first) {
    return (a.second > b.second);
  }
  return (a.first < b.first);
}
int main() {
  int n, h;
  cin >> n >> h;
  vector<pair<int, int> > katana(n);
  vector<int> B(n);
  for (int i = 0; i < n; i++) {
    cin >> katana[i].first >> katana[i].second;
    B[i] = katana[i].second;
  }
  sort(B.begin(), B.end());
  sort(katana.begin(), katana.end(), custom);
  pair<int, int> p = make_pair(katana[n - 1].first, katana[n - 1].second);
  int total = 0;
  int ans = 0;
  for (int i = 0; i < n; i++) {
    if (B[n - 1 - i] >= p.second) {
      total += B[n - 1 - i];
    } else {
      ans += i;
      break;
    }
    if (total >= h) {
      ans += i + 1;
      break;
    }
    if (i == n - 1) ans += i + 1;
  }
  if (total >= h)
    cout << ans << endl;
  else {
    if ((h - total) % p.first == 0)
      cout << ans + (h - total) / p.first << endl;
    else
      cout << ans + (h - total) / p.first + 1 << endl;
  }
}
