#include<bits/stdc++.h>
using namespace std ;
#define leng 50005
int n , h[leng+10001] , mnext[leng+10001] , var[leng+10001] , tot ;
int q = 50005 ;
int hx ;
int t ;
int a ;
int f ;
void add ( int x , int y ){
	mnext[++tot] = h[x] ;
	h[x] = tot ;
	var[tot] = y ;
}
int main ( ){
	cin >> t ;
	for ( int tt = 1 ; tt <= t ; ++tt ){
		cin >> n ;
		tot = 0 ;
		memset ( mnext , 0 , sizeof ( mnext )) ;
		memset( h , 0, sizeof( h ) ) ;
		for ( int j = 1 ; j <= n ; ++j ){
			cin >> a ;
			hx = a % q ;
			f=0 ;
			for ( int i = h[hx] ; i ; i = mnext[i] ){
				if ( var[i] == a ){
					f=1;
					break ;
				}
			}
			if ( f == 0 ){
				cout << a << " " ;
				add ( hx , a ) ;
			}
		}
		cout << endl ;
	}
	return 0 ;
}