#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, h;
  cin >> n >> h;
  vector<pair<int, int> > pa, pb;
  for (int i = 0; i < n; i++) {
    int a, b;
    cin >> a >> b;
    pa.push_back(make_pair(a, i));
    pb.push_back(make_pair(b, i));
  }
  sort(pa.begin(), pa.end());
  sort(pb.begin(), pb.end());
  int af = pa[n - 1].first;
  int as = pa[n - 1].second;
  int sum = 0;
  int hor = 0;
  int th;
  for (int i = n - 1; i >= 0; i--) {
    if (pb[i].second == as) {
      th = i;
      continue;
    }
    if (pb[i].first >= af) {
      hor++;
      sum += pb[i].first;
    }
    if (sum >= h) {
      cout << hor << endl;
      return 0;
    }
    if (pb[i].first < af) {
      break;
    }
  }
  int bf = pb[th].first;
  for (;;) {
    hor++;
    if (sum + bf >= h) {
      cout << hor << endl;
      return 0;
    }
    sum += af;
  }
}
