import java.util.Arrays;
import java.util.Scanner;

public class Main {
   public static void main(String[] args) {
	 Scanner s = new Scanner(System.in) ;
	 int n = s.nextInt() ;
	 for (int i = 0; i < n; i++) {
		int m = s.nextInt() ;
		
		String strs[] = new String[m] ;
		for (int j = 0; j < strs.length; j++) {
			strs[j] = s.next() ;
		}
		Arrays.sort(strs) ;
		for (int j = 0; j < strs.length; j++) {
			System.out.println(strs[j]);
		}
	}
   }
}

/**************************************************************
	Problem: 2220
	User: admin
	Language: Java
	Result: Accepted
	Time:717 ms
	Memory:40108 kb
****************************************************************/