import java.util.Scanner;

public class Task6201116 {


    public  static void main (String[] args){


        int n, drawFirstAst = 1, drawSecondAst=0;
        Scanner scanner = new Scanner(System.in);
        StringBuilder figure = new StringBuilder("");

        n = Integer.parseInt(scanner.nextLine());
     //First Row
        figure.append("@");
        figure.append(strDraw(" ", n-2));
        figure.append("@");
        figure.append(strDraw(" ", n-2));
        figure.append("@\r\n");

        for (int i = 0; i <=n/2 ; i++) {
            if (i>0) {
                drawSecondAst = 1;
            }
            if (i > (n/2)-2){
                drawFirstAst = 0;
                drawSecondAst = 0;
            }
            if (i == n/2) {
                //Row before last 2 Rows
                figure.append("*");
                figure.append(strDraw(".",n/2));
                figure.append(strDraw("*", (n-4)/2));
                figure.append(".");
                figure.append(strDraw("*", (n-4)/2));
                figure.append(strDraw(".",n/2));
                figure.append("*\r\n");
                break;
            }
            figure.append("*");
            figure.append(strDraw(".",i));
            figure.append("*");
            figure.append(strDraw(" ",n-3-(2*i)));
            figure.append(strDraw("*", drawFirstAst));
            figure.append(strDraw(".",2*i-1));
            figure.append(strDraw("*", drawSecondAst));
            figure.append(strDraw(" ",n-3-(2*i)));
            figure.append("*");
            figure.append(strDraw(".",i));
            figure.append("*\r\n");
        }
        //Last Two Rows
        figure.append(strDraw("*", 2*n-1));
        figure.append("\r\n");
        figure.append(strDraw("*", 2*n-1));

        System.out.print(figure.toString());

    }

    public static String strDraw(String strToDraw, int times){
        StringBuilder drawText = new StringBuilder("");
        for (int i = 0; i <times ; i++) {
            drawText.append(strToDraw);
        }
        return drawText.toString();
    }


}