#include <bits/stdc++.h>
using namespace std;
long long a[100005], b[100005], sumb[100005] = {0};
int main() {
  long long n, y;
  while (scanf("%lld%lld", &n, &y) == 2) {
    long long imax = -411111111, sum = 0;
    for (int i = 1; i <= n; i++) {
      scanf("%d%d", &a[i], &b[i]);
      if (a[i] > imax) imax = a[i];
    }
    int num = 0;
    for (int i = 1; i <= n; i++) {
      if (imax <= b[i]) {
        sum += b[i];
        num++;
      }
    }
    y = y - sum;
    int r = y / imax;
    if (r * imax < y) r++;
    num += r;
    printf("%d\n", num);
  }
}
