#include <bits/stdc++.h>
using namespace std;
const int N = 1e6;
long long n, h, cnt, ans, a;
pair<long long, long long> p[N];
int main() {
  scanf("%d%d", &n, &h);
  for (int i = 0; i < n; i++) {
    scanf("%d %d", &p[i].first, &p[i].second);
  }
  sort(p, p + n);
  reverse(p, p + n);
  for (int i = 0; i < n; i++) {
    if (p[0].first < p[i].second) {
      cnt += p[i].second;
      a++;
    }
  }
  if (cnt >= h) {
    return cout << n, 0;
  } else {
    long long k = h - cnt;
    ans = a + (k / p[0].first);
    return cout << ans, 0;
  }
}
