#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int a, b, k[100000], l[100000], sum = 0, count = 0;
  cin >> a >> b;
  for (int i = 0; i < a; ++i) {
    cin >> k[i] >> l[i];
  }
  long long int lim = a;
  sort(k, k + a);
  reverse(k, k + a);
  sort(l, l + a);
  reverse(l, l + a);
  for (int i = 0; i < a; ++i) {
    if (l[i] > k[0] && b > 0 && lim > 0) {
      sum += l[i];
      b -= l[i];
      ++count;
      --lim;
    } else
      break;
  }
  if (b % k[0] == 0)
    count += b / k[0];
  else
    count += b / k[0] + 1;
  cout << count << endl;
}
