using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Saisir un nombre");

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

 int i=1;

     int m = i;

     for (i=1; i<n+1; i++)

     {

         m=m*i;

       }

        Console.WriteLine(n+ " a pour factorielle " +m);

    }

}