#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using ll=long long;
using Graph=vector<vector<int>>;
#define INF 1000000000
#define MOD 998244353
#define MAX 200000

int main(){
  int a,b;
  cin>>a>>b;
  int n=a|b;
  ll ans=1;
  for(int i=1;i<=n;i++){
    ans*=(ll)i;
  }
  cout<<ans<<'\n';
}