using System;

public class Program

{

    public static void Main()

    {

        int layer = 20;

        Console.WriteLine("This is a {0} layer Pyramid !",layer);

        Console.WriteLine();

        //PrintLinearPyramid(layer);

        PrintProperPyramid(layer);

    }

    private static bool isEven(int number)

    {

        return number % 2 == 0; 

    }

    private static void PrintLinearPyramid(int layer)

    {

        for(int index = 1; index< layer+1; index++) 

        {

            for(int hit=1; hit< index+1 ; hit++)

            {

                Console.Write("*");

            }

            Console.WriteLine();

        }

    }

    private static void PrintProperPyramid(int layer)

    {

        for(int verIndex = 0; verIndex < layer; verIndex++)

        {

            for(int horIndex = 0; horIndex< (2*layer)-1; horIndex++)

            {

                if(horIndex < ((layer-1)-verIndex) || horIndex > ((layer-1)+ verIndex)) Console.Write(" ");

                else

                {

                    if(horIndex == ((layer-1)-verIndex) || horIndex == ((layer-1) + verIndex)) 

                    {

                        Console.Write("*");

                    }

                    else

                    {

                        if(!isEven(layer))

                        {

                            if((isEven(horIndex)&isEven(verIndex)) || (!isEven(horIndex)&!isEven(verIndex)) )

                            {

                                Console.Write("*");

                            }

                            else

                            {

                                Console.Write(" ");

                            }

                        }

                        else

                        {

                            if((isEven(horIndex)&isEven(verIndex)) || (!isEven(horIndex)&!isEven(verIndex)) )

                            {

                                Console.Write(" ");

                            }

                            else

                            {

                                Console.Write("*");

                            }

                        }

                    }                   

                }

            }

            Console.WriteLine();            

        }

    }

}