#include <bits/stdc++.h>
using namespace std;
int n, h;
pair<int, int> d[100005];
int main() {
  cin >> n >> h;
  int maxd = 0;
  for (int i = 0; i < n; i++)
    cin >> d[i].second >> d[i].first, maxd = max(maxd, d[i].second);
  sort(d, d + n);
  long long sum = 0;
  for (int i = 0; i < n; i++) {
    sum += d[i].first;
    if (sum >= h) {
      cout << i + 1;
      return 0;
    }
  }
  h -= sum;
  cout << h / maxd + (h % maxd != 0 && n <= 1) + n;
  return 0;
}
