using System;

public class Program

{

    public static void Main()

    {

        for(byte count=1; count<=5; count++)

        {

            for(byte i=1; i<=10; i++)

            {

                Console.WriteLine(i);           

            }

            for(byte i=10; i>=1; i--)

            {

                Console.WriteLine(i);           

            }

        }

    }

}