using System;

public class Program

{

    public static void Main()

    {

        start:

        Console.WriteLine("Introduce a number: ");

        int n1 = Convert.ToInt32(Console.ReadLine());

        int factorial = 1;

​

        Console.Write("{0}! = ", n1);

        for (int i = 1; i <= n1; i++)

        {

            factorial *= i;

            Console.Write("{0} ", i);

            if (i<n1)

                Console.Write("x");

        }

        Console.Write("= {0} ", factorial);

    }

}