Eggcelent

using System;

class Eggcelent
{
    static void Main()
    {
        int n = int.Parse(Console.ReadLine());
        int width = n * 3 + 1;
        int height = 2 * n;
        int dotCounter = n + 1;
        int counter = 0;


        //first line --> special
        Console.Write(new string('.', dotCounter));
        Console.Write(new string ('*', n-1));
        Console.WriteLine(new string('.', dotCounter));

        //top
        int innterDotCounter = 0;
        if (n == 2)
        {
            innterDotCounter = 3;
        }
        else
        {
            innterDotCounter = n - 3;
            for (int i = n - 1; i >= 1; i -= 2)
            {
                innterDotCounter += 4;
                dotCounter -= 2;
                Console.Write(new string('.', dotCounter));
                Console.Write('*');
                Console.Write(new string('.', innterDotCounter));
                Console.Write('*');
                Console.WriteLine(new string('.', dotCounter));
                counter++;
            }
        }

    //special part
        int specialCounter = (2 * n - (4 + 2 * counter)) / 2;
        if (specialCounter > 0)
        {
            for (int i = 0; i < specialCounter; i++)
            {
                Console.Write(".*");
                Console.Write(new string('.', width - 4));
                Console.WriteLine("*.");
            }
        }

        //middle
        Console.Write(".*");
        for (int i = 1; i <= (innterDotCounter - 1) / 2; i++)
        {
            Console.Write("@.");
        }
        Console.Write('@');
        Console.WriteLine("*.");

        Console.Write(".*");
        for (int i = 1; i <= (innterDotCounter - 1) / 2; i++)
        {
            Console.Write(".@");
        }
        Console.Write('.');
        Console.WriteLine("*.");

        //special part
        if (specialCounter > 0)
        {
            for (int i = 0; i < specialCounter; i++)
            {
                Console.Write(".*");
                Console.Write(new string('.', width - 4));
                Console.WriteLine("*.");
            }
        }

        //bottom
        if (n == 2)
        {
            innterDotCounter = 3;
        }
        else
        {
            for (int i = 1; i <= n - 1; i += 2)
            {
                Console.Write(new string('.', dotCounter));
                Console.Write('*');
                Console.Write(new string('.', innterDotCounter));
                Console.Write('*');
                Console.WriteLine(new string('.', dotCounter));
                dotCounter += 2;
                innterDotCounter -= 4;
            }
        }
        //last line == first line
        Console.Write(new string('.', n + 1));
        Console.Write(new string('*', n - 1));
        Console.WriteLine(new string('.', n + 1));




    }
}