#include <bits/stdc++.h>
using namespace std;
const int64_t MOD = 1000000007;
long long gcd(long long a, long long b) {
  int64_t gcdmax = max(a, b);
  int64_t gcdmin = min(a, b);
  while (true) {
    if (gcdmax % gcdmin == 0)
      break;
    else
      gcdmax %= gcdmin;
    swap(gcdmin, gcdmax);
  }
  return gcdmin;
}
int64_t powerup(int64_t N, int64_t P, int64_t M) {
  if (P == 0)
    return 1;
  else if (P % 2 == 0) {
    int64_t t = powerup(N, P / 2, M);
    return t * t % M;
  } else
    return N * powerup(N, P - 1, M) % M;
}
vector<int64_t> find_divisor(int64_t N) {
  int64_t k = 1;
  while (k * k <= N) {
    k++;
  }
  vector<int64_t> A(1);
  for (int64_t i = 0; i < (int64_t)(k); i++) {
    if (i == 1)
      A.at(0) = 1;
    else if (i >= 2) {
      if (N % i == 0) A.push_back(i);
    }
  }
  int64_t t = 0;
  t = A.size();
  for (int64_t i = 0; i < (int64_t)(t); i++) {
    if (A.at(t - i - 1) * A.at(t - i - 1) != N)
      A.push_back(N / A.at(t - 1 - i));
  }
  return A;
}
int main() {
  int64_t N, H;
  cin >> N >> H;
  vector<int64_t> A(N);
  vector<int64_t> B(N);
  for (int64_t i = 0; i < (int64_t)(N); i++) {
    cin >> A.at(i) >> B.at(i);
  }
  int64_t sum = 0;
  int64_t Z = 0;
  sort(A.begin(), A.end(), greater<int64_t>());
  sort(B.begin(), B.end(), greater<int64_t>());
  int64_t ans = (H - 1) / A.at(0) + 1;
  for (int64_t i = 0; i < (int64_t)(N); i++) {
    sum += B.at(i);
    ans = min(ans, (H - sum - 1) / A.at(0) + 2 + i);
  }
  cout << ans << endl;
}
