#include<iostream>
#include<cstdlib>
#include<cstring>
using namespace std;

int main() {
    int n;
    cin >> n;

    for(int i = 0; i < n; i++){
        int num;
        cin >> num;

        int *q = new int[num];
        bool *st = new bool[num];
        memset(st, false, sizeof(bool) * num);

        for(int i = 0; i < num; i++){
            cin >> q[i];
            st[q[i]] = true;
        }

        for(int i = 0; i < num; i++){
            if(st[q[i]] == true)
                cout << q[i] << ' ';
            st[q[i]] = false;
        }

        cout << endl;

        delete[] q;
        delete[] st;
    }

    return 0;
}