#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
int main() {
    int trick, treat;
    cin >> trick >> treat;

    // Calculate
    int x = trick | treat;
    long long ans = 1;
    rep(i, x) ans *= i + 1;

    // Output
    cout << ans << endl;
}