#include <bits/stdc++.h>
using namespace std;
using vi = vector<int>;
using vii = vector<vi>;
using pii = pair<int, int>;
using vpii = vector<pii>;
int main() {
  int n, h;
  cin >> n >> h;
  vi a(n), b(n);
  for (int i = 0; i < (int)(n); i++) cin >> a[i] >> b[i];
  sort(a.begin(), a.end());
  sort(b.begin(), b.end());
  int c = 0;
  while (h > 0) {
    int k = b.size();
    if (a[n - 1] >= b[k - 1]) {
      h -= a[n - 1];
      c++;
    } else {
      h -= b[k - 1];
      b.erase(b.end());
    }
    if (b.empty()) break;
  }
  while (h > 0) {
    h -= a[n - 1];
    c++;
  }
  cout << c << endl;
}
