class Program
{

    static void Main(string[] args)
    {
        int consoleInput = int.Parse(Console.ReadLine());
        int result = consoleInput;

        for (int i = 1; i < consoleInput; i++)
        {
            result = result * i;
        }

        Console.WriteLine(result);

    }

}

class Program
{

    static void Main(string[] args)
    {
        int consoleInput = int.Parse(Console.ReadLine());
        int result = consoleInput;

        for (int i = 1; i < consoleInput; i++)
        {
            result = result * i;
        }

        Console.WriteLine(result);

    }

}