#include <bits/stdc++.h>
using namespace std;
const long long MOD = 1000000007;
const long long INF = 1000000000;
template <typename T1, typename T2>
inline void chmin(T1 &a, T2 b) {
  if (a > b) a = b;
}
template <typename T1, typename T2>
inline void chmax(T1 &a, T2 b) {
  if (a < b) a = b;
}
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  int n, h;
  cin >> n >> h;
  vector<int> a(n), b(n);
  int amax = 0;
  for (int i = 0; i < n; ++i) {
    cin >> a[i] >> b[i];
    chmax(amax, a[i]);
  }
  sort(b.begin(), b.end(), greater<int>());
  int ans = 0;
  for (int i = 0; i < n; ++i) {
    if (b[i] >= amax && h > 0) {
      ++ans;
      h -= b[i];
    } else
      break;
  }
  ans += h / amax + (h % amax);
  cout << ans << endl;
  return 0;
}
