#include <bits/stdc++.h>
using namespace std;

int main()
{
  int64_t trick, treat;
  cin >> trick >> treat;
  
  int64_t check = trick | treat;
  int64_t ans = 1;
  for(int64_t i = 1; i <= check; i++) ans *= i;
  cout << ans << endl;
  return 0;
}