#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <utility>
#include <map>
#include <set>
#include <queue>
#include <iomanip>
#include <cstring>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
typedef long long ll;
#define rep(i,n) for (int i = 0; i < int(n);i++)

int main(){
  ll a,b;
  cin >> a >> b;
  ll ans = 1LL;
  for (int i = 1; i <= (a | b);i++){
    ans *= i;
  }
  cout << ans << endl;
  return 0;
}