import java.util.Scanner;
 
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int rt = sc.nextInt();
        while(rt>0){
            int rn = sc.nextInt();
 
            for (int i = 1; i <= rn; i++) {
                for (int j = 1; j <= rn; j++) {
                    System.out.print("##");
                }
                for (int j = 1; j <= rn; j++) {
                    System.out.print("..");
                }
                System.out.println();
            }
 
            rt--;
        }
    }
}

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

NAoxCjIKMwo0Cg==

4
1
2
3
4