#include <bits/stdc++.h>
using namespace std;
const int INF = 1 << 29;
pair<int, int> p1[111111], p2[111111];
bool cmp1(pair<int, int> a, pair<int, int> b) { return a.first > b.first; }
bool cmp2(pair<int, int> a, pair<int, int> b) { return a.second > b.second; }
int main() {
  ios::sync_with_stdio(0);
  int a, b, h, n;
  long long count = 0LL;
  cin >> n >> h;
  for (int i = 0; i < n; i++) {
    cin >> p1[i].first >> p1[i].second;
    p2[i].first = p1[i].first;
    p2[i].second = p1[i].second;
  }
  if (n > 1) {
    sort(p1, p1 + n, cmp1);
    sort(p2, p2 + n, cmp2);
  }
  int j = 0;
  while (p2[j].second >= p1[0].first && j < n && h > 0) {
    h -= p2[j].second;
    count++;
    j++;
  }
  if (h > 0) count += (h / p1[0].first);
  cout << count << endl;
  return 0;
}
