#include <bits/stdc++.h>
const int INF = 1 << 30;
const long long LINF = 1LL << 60;
const long long int MOD = 1000000007;
using namespace std;
using ll = long long;
using P = pair<int, int>;
template <class T>
inline bool chmin(T& a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <class T>
inline bool chmax(T& a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
ll h;
ll max_a;
int main() {
  cin.tie(nullptr);
  ios::sync_with_stdio(false);
  ll n;
  cin >> n >> h;
  vector<ll> a(n, 0);
  vector<ll> b(n, 0);
  for (long long i = 0; i < (n); ++i) {
    cin >> a[i] >> b[i];
  }
  max_a = *max_element(a.begin(), a.end());
  sort(b.begin(), b.end(), greater<ll>());
  vector<ll> sum(n + 1, 0);
  for (long long i = (1); i < (n + 1); i++) {
    if (b[i - 1] < max_a) {
      sum.resize(i);
      break;
    }
    sum[i] = sum[i - 1] + b[i - 1];
  }
  ll res = LINF;
  for (long long i = (1); i < (sum.size()); i++) {
    ll r = 0;
    r += (i);
    ll remain = h - sum[i];
    r += (remain + max_a - 1) / max_a;
    chmin(res, r);
  }
  cout << res << "\n";
  return 0;
}
