#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
#include <queue>
#include <map>
#include <cmath>
#include <iomanip>
#include <set>
#include <cstdio>

using namespace std;

int main() {
  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;
}