#include <bits/stdc++.h>
using namespace std;
int n, h, b[10010], maxa = 1, x;
int main() {
  scanf("%d%d", &n, &h);
  for (int i = 0; i < n; ++i) {
    scanf("%d%d", &x, &b[i]);
    maxa = max(x, maxa);
  }
  sort(b, b + n);
  auto lb = lower_bound(b, b + n, maxa);
  int idx = lb - b;
  int s = 0;
  for (int i = idx; i < n; ++i) {
    s += b[i];
    if (s >= h) {
      printf("%d\n", i - idx + 1);
      return 0;
    }
  }
  h -= s;
  int prestep = h / maxa;
  int secstep = n - idx;
  if (h % maxa != 0) ++prestep;
  printf("%d\n", prestep + secstep);
  return 0;
}
