1 import java.util.Scanner; 2  3 public class Main { 4  5     public static void main(String[] args) { 6          7          8         Scanner sc=new Scanner(System.in); 9         10         int times=sc.nextInt();11         while(times-->0){12             13             int n=sc.nextInt();14             int book[]=new int[100];15             16             for(int i=0;i<n*2;i++){17                 book[sc.nextInt()]=1;18             }19 20             for(int i=0;i<book.length;i++){21                 if(book[i]==1) System.out.print(i+" ");22             }23             System.out.println();24             25         }26         27     }28     29 }