#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, h, a[100050], b[100050], amax = 0, bmax = 0, sum = 0, katana;
  cin >> n >> h;
  for (int i = 1; i <= n; i++) {
    cin >> a[i] >> b[i];
  }
  int nn = n;
  int hh = h;
  while (nn && hh) {
    bmax = 0;
    for (int i = 1; i <= n; i++) {
      if (b[i] > b[bmax]) bmax = i;
    }
    hh -= b[bmax];
    b[bmax] = 0;
    nn--;
    sum++;
  }
  if (hh) {
    for (int i = 1; i <= n; i++) {
      if (a[i] > a[amax]) amax = i;
      if (b[i] > b[bmax]) bmax = i;
    }
    katana = a[amax];
    a[amax] = 0;
    while (h) {
      if (n)
        h -= b[bmax];
      else
        h -= a[amax];
      sum++;
    }
    cout << sum << endl;
  } else {
    cout << sum << endl;
  }
  return 0;
}
