#include <bits/stdc++.h>
using namespace std;
int n;
long long h, ans;
double tmp;
int main(int argc, char const* argv[]) {
  cin >> n >> h;
  priority_queue<pair<long, long> > katana;
  vector<long long> slashes(n);
  long long a, b, ans = 0, throwdamage, slashdamage;
  for (int i = 0; i < n; i++) {
    cin >> a >> b;
    katana.push(make_pair(b, a));
    slashes[i] = a;
  }
  sort(slashes.begin(), slashes.end(), greater<long long>());
  slashdamage = slashes[0];
  for (int i = 0; i < n; i++) {
    throwdamage = katana.top().first;
    katana.pop();
    if (throwdamage >= slashdamage) {
      h -= throwdamage;
      ans++;
      if (h <= 0) break;
    }
  }
  if (h <= 0) {
    cout << ans << endl;
    return 0;
  } else {
    ans += h / slashdamage;
    tmp = (h + 0.0) / (slashdamage + 0.0);
    if (tmp > ans) ans++;
  }
  cout << ans << endl;
  return 0;
}
