#include <bits/stdc++.h>
using namespace std;

const int MAXN = 1e5;

int T;

void re()
{
	int n,m;
	map<int,int > pos;
	vector<int> num;
	cin >> n;
	for(int i = 1;i <= n;i++)
	{
		cin >> m;
		if(pos[m] == 0)
		{
			pos[m] ++;
			num.push_back(m);
		}
	}
	for(int i = 0;i < (int)num.size();i++)
	{
		cout << num[i] << " "; 
	}
	cout << endl;
	return ;
}

int main()
{
	cin >> T;
	while(T--)
	{
		re();
	}
	return 0;
}