#include <bits/stdc++.h>
using namespace std;
int main() {
  int long long n, h;
  cin >> n >> h;
  vector<int long long> a(n);
  vector<int long long> b(n);
  for (int i = 0; i < n; i++) {
    int long long x, y;
    cin >> x >> y;
    a.push_back(x);
    b.push_back(y);
  }
  sort(a.rbegin(), a.rend());
  sort(b.rbegin(), b.rend());
  int long long nage = 0;
  int long long nokori = 0;
  int long long ans = 0;
  int long long mi = h / a[0];
  if (h % a[0] != 0) mi++;
  for (int long long i = 0; i < n; i++) {
    nage += b[i];
    nokori = h - nage;
    if (nokori >= 0) {
      ans = nokori / a[0];
      if (nokori % a[0] != 0) ans++;
      ans += i + 1;
      mi = min(ans, mi);
    }
  }
  cout << mi << endl;
  return 0;
}
