#include<algorithm>
#include<cstring>
#include<string>
#include<map>
#include<queue>
#include<stack>
#include<vector>
#include<cmath>
#define x first
#define y second
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
const int maxn=2e4+34;
int inf=0x3f3f3f3f;
int idx,cnt,tot;
map<ll,ll>vis;
ll read(){
    ll res=0;
    char ch=getchar();
    while(!isdigit(ch))ch=getchar();
    while(isdigit(ch)){
        res=res*10+ch-'0';
        ch=getchar();
    }
    return res;
}
void write(ll x){
    if(x>=10)write(x/10);
    putchar(x%10+'0');
}
void work(){
	ll n=read(),x;
	vis.clear();
	for(int i=1;i<=n;i++){
		x=read();
		if(vis[x])continue;
	    write(x);
	    putchar(' ');
		vis[x]++;
	}
	putchar('\n');
}
int main()
{
	int t=1;
	t=read();
	while(t--)
    work();
    return 0;
}```