#include <bits/stdc++.h>
using namespace std;
using P = pair<long long, long long>;
using V = vector<long long>;
void solve_abc() {
  long long n, h;
  long long ans = 0;
  cin >> n >> h;
  vector<P> a(n), b(n);
  V ob(n);
  long long ta, tb, ti;
  for (long long i = 0; i < (long long)(n); i++) {
    cin >> ta >> tb;
    a[i] = make_pair(ta, i);
    b[i] = make_pair(tb, i);
    ob[i] = tb;
  }
  sort((a).begin(), (a).end());
  reverse((a).begin(), (a).end());
  sort((b).begin(), (b).end());
  reverse((b).begin(), (b).end());
  ta = a[0].first;
  ti = a[0].second;
  tb = ob[ti];
  long long now = 0;
  for (long long i = 0; i < (long long)(n); i++) {
    if (b[i].first > ta) {
      if (b[i].second != ti) {
        now += b[i].first;
        ans++;
        if (h <= now) {
          break;
        }
      }
    } else {
      break;
    }
  }
  h -= now;
  long long val;
  if (h > 0) {
    if (ta > tb) {
      val = h / ta;
      ans += val;
      if (h - ta * val > 0) {
        ans++;
      }
    } else {
      h -= tb;
      ans++;
      if (h > 0) {
        val = h / ta;
        ans += val;
        if (h - ta * val > 0) {
          ans++;
        }
      }
    }
  }
  cout << ans << "\n";
}
int main(void) {
  cin.tie(0);
  ios::sync_with_stdio(false);
  solve_abc();
  return 0;
}
