#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int n, h, i, maxi = 0, maxi2 = 0, c = 0, sum = 0, in;
  cin >> n >> h;
  vector<long long int> v;
  for (i = 0; i < n; i++) {
    long long int x, y;
    cin >> x >> y;
    if (x > maxi) {
      maxi = x;
      maxi2 = y;
      in = i;
    }
    if (x == maxi) {
      if (y <= maxi2) {
        maxi = x;
        maxi2 = y;
        in = i;
      }
    }
    v.push_back(y);
  }
  sort(v.rbegin(), v.rend());
  for (i = 0; i < n; i++) {
    sum = sum + v[i];
    if (sum >= h) {
      c = i + 1;
      break;
    }
  }
  if (c != 0) {
    cout << c << endl;
  } else {
    for (i = 0; i < n; i++) {
      if (v[i] >= maxi) {
        h = h - v[i];
        c++;
      }
    }
    if (h % maxi == 0)
      cout << c + (h / maxi) << endl;
    else
      cout << c + 1 + (h / maxi) << endl;
  }
  return 0;
}
