#include <iostream>
#include <cassert>

using namespace std;

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  int a, b; cin >> a >> b;
  int c = a | b;
  long long ans = 1;
  for (int i = c; i > 1; i--) {
    ans *= (long long)i;
  }
  cout << ans << endl;
  return 0;
}