using System.Numerics;

public class Program
{
    public static void Main()
    {

        //int num = int.Parse(Console.ReadLine() ?? string.Empty);
        string[] str = (Console.ReadLine() ?? string.Empty).Trim().Split(' ');
        //string str = Console.ReadLine() ?? string.Empty;

        int a = int.Parse(str[0]);
        int b = int.Parse(str[1]);

        double d = (a | b)!;

        int count = 1;
        for(int i = 1; i<=d;i++)
        {
            count *= i;
        }
        Console.WriteLine(count);
    }
}