#include <bits/stdc++.h>
using namespace std;
const long long N = 1e6 + 55, mod = 1e9 + 7;
vector<long long> aa, bb;
int main() {
  long long ans = mod, k, n, h, i, j, a, b, c, x, y, z;
  scanf("%lld", &n);
  scanf("%lld", &h);
  aa.push_back(-1);
  bb.push_back(mod);
  for (i = 1; i <= n; i++) {
    scanf("%lld", &a);
    scanf("%lld", &b);
    aa.push_back(a);
    bb.push_back(b);
  }
  sort(bb.rbegin(), bb.rend());
  bb[0] = 0;
  for (i = 1; i <= n; i++) {
    bb[i] += bb[i - 1];
  }
  j = *max_element(aa.begin(), aa.end());
  k = lower_bound(bb.begin(), bb.end(), h) - bb.begin();
  if (k > n) k = n;
  c = mod;
  while (k > 0) {
    b = h - bb[k];
    if (b < 0) b = 0;
    a = b / j;
    ans = min(ans, a + k);
    k--;
  }
  printf("%lld\n", ans);
}
