#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
constexpr int inf = 1 << 30;
constexpr int mo = 1e9 + 7;
constexpr ll infl = 1ll << 60;
int main() {
  cin.tie(nullptr);
  ios::sync_with_stdio(false);
  int n, h;
  cin >> n >> h;
  vector<int> v;
  int ma = 0;
  for (int i = 0; i < n; ++i) {
    int a, b;
    cin >> a >> b;
    ma = max(ma, a);
    v.emplace_back(b);
  }
  sort(v.rbegin(), v.rend());
  vector<ll> s(n + 1);
  s[0] = v[0];
  for (int i = 1; i < n; ++i) s[i] += s[i - 1] + v[i];
  ll ret = (h + ma - 1) / ma;
  for (int i = 0; i < n; ++i) {
    if (v[i] <= ma) break;
    ll tmp = 0;
    tmp += i + 1;
    tmp += (h - s[i] + ma - 1) / ma;
    ret = min(ret, tmp);
  }
  cout << ret << endl;
  return 0;
}
