using System;

public class Program

{

    public static void Main()

    {

        int i,no,fact=1;

        Console.WriteLine("Enter a number");

        no=int.Parse(Console.ReadLine());

        for(i=1;i<=no;i++)

        {

            fact=fact*i;

        }

        Console.WriteLine("Factorial of no is :"+fact);

    }

}