#include <bits/stdc++.h>
using namespace std;
int a[100000002], b[100000002];
int n, h, m;
int main() {
  cin >> n >> h;
  for (int i = 0; i <= n - 1; i++) cin >> a[i] >> b[i];
  sort(a, a + n);
  sort(b, b + n);
  for (int i = n - 1; i >= 0; i--) {
    if (a[n - 1] < b[i])
      h -= b[i];
    else
      h -= a[n - 1];
    if (h <= 0) {
      cout << n - i + 1;
      system("pause");
      return 0;
    }
  }
  while (h > 0) {
    h -= a[n - 1];
    m++;
    if (h <= 0) {
      cout << m + n;
    }
  }
  system("pause");
  return 0;
}
