#include<iostream>
#include<unordered_map>
using namespace std;
unordered_map<int,int> a;
int ax[50001];
void read(int &x) { //快读
	int f = 1;
	x = 0;
	char ch = getchar();
	while (ch < '0' || ch > '9') {
		if (ch == '-') f = -1;
		ch = getchar();
	}
	while (ch >= '0' && ch <= '9') {
		x = x * 10 + ch - '0';
		ch = getchar();
	}
	x *= f;
}
int main(){
	int t;
	read(t);
	for(int i=0;i<t;i++){
		int n;
		read(n);
		a.clear();
		for(int j=0;j<n;j++){
			ax[j]=0;
		}
		for(int j=0;j<n;j++){
			int x;
			read(x);
			if(!a.count(x)){
				a[x]=1;
				ax[j]=x;
			}
		}
		for(int j=0;j<n;j++){
			if(ax[j])cout<<ax[j]<<" ";
		}
		cout<<endl;
	}
	return 0;
}

求助！希望有大佬多多指教，帮助必关！(*￣3￣)╭