#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vi = vector<int>;
using vvi = vector<vi>;
using vl = vector<ll>;
using vs = vector<string>;
using P = pair<int, int>;
using T = tuple<int, int, int>;
using vp = vector<P>;
using vt = vector<T>;
const int mod = 1000000007;
const double EPS = 1e-9;
const ll INF = (1LL << 62) - 1;
inline int in() {
  int x;
  scanf("%d", &x);
  return x;
}
template <typename T>
inline ll suma(const vector<T>& a) {
  ll res(0);
  for (auto&& x : a) res += x;
  return res;
}
template <class T>
inline bool chmax(T& a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T>
inline bool chmin(T& a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
int main() {
  ll n, h;
  cin >> n >> h;
  vl a(n), b(n);
  for (int i = (0); i < (n); ++i) cin >> a[i] >> b[i];
  sort(b.rbegin(), b.rend());
  ll ma = *max_element((a).begin(), (a).end());
  ll ans = 0;
  for (int i = (0); i < (n); ++i) {
    if (h <= 0) break;
    if (b[i] > ma)
      ans++;
    else
      break;
  }
  if (h > 0) ans += (((h) + (ma)-1) / (ma));
  cout << ans << endl;
  return 0;
}
