using System;
using System.Collections.Generic;
using static System.Console;
using System.Linq;

class yuki319
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(int n) => Enumerable.Repeat(0, n).Select(_ => NList).ToArray();
    static void Main()
    {
        var c = NList;
        var res = 1L;
        for (var i = 1; i <= (c[0] | c[1]); ++i) res *= i;
        WriteLine(res);
    }
}