#include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define fr first
#define se second
#define FAST ios::sync_with_stdio(false), cin.tie(0), cout.tie(0)
using namespace std;
int t,n;
const ll l=-54088;
struct number{
	ll num,sum;
}a[50005];
bool cmps(number x,number y){
	return x.sum<y.sum;
}
bool cmpn(number x,number y){
	return x.num<y.num;
} 
void breaksame(){
	for(int i=1;i<=n;i++){
		for(int j=i+1;j<=n;j++){
			if(a[i].sum==a[j].sum){
				a[j].sum=l;
			}
		}
	}
}
int main(){
	FAST;
	cin>>t;
	while(t--){
		cin>>n;
		for(int i=1;i<=n;i++){
			cin>>a[i].sum;
			a[i].num=i;
		}
		sort(a+1,a+1+n,cmps);
		breaksame();
		sort(a+1,a+1+n,cmpn);
		for(int i=1;i<=n;i++){
			if(a[i].sum!=l) cout<<a[i].sum<<" ";
		}
		cout<<endl;
	}
	return 0;
}