#include "bits/stdc++.h"

#define REP(i, m, n) for (int i = (int)(m); i < (int)(n); ++i)
#define rep(i, n) REP(i, 0, n)
#define all(x) (x).begin(), (x).end()
using namespace std;
typedef long long ll;
const long long mod = 1e9 + 7;

int stoi(const char c) {
  switch (c) {
    case '0':
      return 0;
    case '1':
      return 1;
    case '2':
      return 2;
    case '3':
      return 3;
    case '4':
      return 4;
    case '5':
      return 5;
    case '6':
      return 6;
    case '7':
      return 7;
    case '8':
      return 8;
    case '9':
      return 9;
    default:
      return -1;
  }
}

int main() {
  ll n, h, ans = 0;
  cin >> n >> h;
  vector<ll> a(n), b(n);
  rep(i, n) cin >> a[i] >> b[i];
  sort(all(a), greater);
  sort(all(b), greater);

  rep(i, n) {
    if (b[i] > a[n - 1]) {
      h -= b[i];
      ans++;
      if (h <= 0) {
        cout << ans;
        return 0;
      }
    } else {
      break;
    }
  }
  ans += h / a[n - 1];
  if (h % a[n - 1] != 0) ans++;

  cout << ans;
  return 0;

  return 0;
}
