#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
using namespace std;
using ll = long long;
using pii = pair<int, int>;
using pll = pair<long long, long long>;
constexpr char ln = '\n';
constexpr long long MOD = 1000000007LL;
constexpr long long INF = 1000000009LL;
template <class T>
inline bool chmax(T& a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
inline bool chmin(T& a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}
int main() {
  int n, h;
  cin >> n >> h;
  vector<ll> A(n), B(n);
  for (int i = 0; i < (n); i++) cin >> A[i] >> B[i];
  sort((A).begin(), (A).end()), sort((B).begin(), (B).end(), greater<ll>());
  ll throw_ = 0;
  int res = INF;
  for (int i = 0; i <= n; i++) {
    int slash_ = h - throw_;
    int num = slash_ / A[n - 1] + i;
    if (slash_ > 0 && slash_ % A[n - 1]) num++;
    chmin(res, num);
    if (i < n) throw_ += B[i];
  }
  cout << res << ln;
}
