Триъгълник

import java.util.Scanner;

public class demo {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

       int n = Integer.parseInt(scanner.nextLine());

       String firstline = repeatStr("#", n * 4 + 1);
        System.out.println(firstline);

        for (int i = 0; i < n; i++) {
            String line = repeatStr(".", 1 + i)
                    + repeatStr("#", (2 * n - 1) - i * 2)
                    + repeatStr(" ", 1 + i * 2)
                    + repeatStr("#", (2 * n - 1) - i * 2)
                    + repeatStr(".", 1 + i);

            if(i == n / 2){
                line = repeatStr(".", 1 + i)
                        + repeatStr("#", (2 * n - 1) - i * 2)
                        + repeatStr(" ", (1 + i * 2) / 2 - 1)
                        + "(@)"
                        + repeatStr(" ", (1 + i * 2) / 2 - 1)
                        + repeatStr("#", (2 * n - 1) - i * 2)
                        + repeatStr(".", 1 + i);

            }
            System.out.println(line);

        }
        for (int i = 0; i < n; i++) {
            String lastPart = repeatStr(".", n + 1 + i)
                    + repeatStr("#", n * 2 - 1 - 2 * i)
                    + repeatStr(".", n + 1 + i);
            System.out.println(lastPart);
        }

    } public static String repeatStr(String strToRepeat, int count) {
        String text = "";
        for (int i = 0; i < count; i++) {
            text += strToRepeat;
        }
        return text;
    }
}