#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<vi> vvi;
typedef pair<int, int> P;

#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define print(x) cout << x << endl
#define all(v) (v).begin(),(v).end()
#define YN(ok) print((ok ? "YES" : "NO"))
#define yn(ok) print((ok ? "Yes" : "No"))
#define decimal(n) setprecision(25) << n

#define Arrays_toString(v) rep(o,(v).size()){cout<<v[o]<<", ";if(o==(v).size()-1){cout<<endl;}}

int main(void){
    int a, b; cin >> a >> b;
    int res = a | b;
    
    ll res2 = 1;
    rep(i, res+1) {
        if (i == 0) continue;
        res2 *= i;
    }
    print(res2);
}