using System;

public class Program

{

​

       public static void Main(string[] args)

        {

            int x = 9; // Total Number of Lines...

            // Print simple pyramid..

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

            {

                // Loop For Space

                for (int j = 1; j <= (x - i); j++)

                    Console.Write(" ");

                //increase the number value

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

                    Console.Write(Number);

                //decrease the number value

                for (int Number = (i - 1); Number >= 1; Number--)

                    Console.Write(Number);

                Console.WriteLine();

            }

            //Print reverse pyramid..

            for (int i = (x - 1); i >= 1; i--)

            {

                // Loop For Space

                for (int j = 1; j <= (x - i); j++)

                    Console.Write(" ");

                //increase the number value

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

                    Console.Write(Number);

                //decrease the number value

                for (int Number = (i - 1); Number >= 1; Number--)

                    Console.Write(Number);

                Console.WriteLine();

            }

            Console.ReadLine();

        }

    }

​

​

//Here I used 2 nested for loop , one to print the simple pyramid ( with x rows ) and another to print the reverse pyramid pattern ( with x-1 rows ).

​