#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i,m,n) for(int i=m; i<n; ++i)
#define repl(i,m,n) for(ll i=m; i<n; ++i)

ll fact(ll N){
    ll res = 1LL;
    for(ll i = 2; i <= N; ++i){
        res *= i; 
    }
    return res;
}

int main(){
    ll a, b;
    cin >> a >> b;
    cout << fact(a | b) << endl;
    return 0;
}