//{ Driver Code Starts
#include<bits/stdc++.h>
using namespace std;
// } Driver Code Ends
class Solution
{
public:
vector<int> singleNumber(vector<int> arr)
{
vector<int> ans;
int XOR=arr[0];
for(int i=0;i<arr.size();i++){
XOR=XOR ^ arr[i]; //get xor of 2 unique umbers
}
int right_bit =XOR & ~(XOR-1);
int x=0,y=0;
for(int i=0;i<arr.size();i++){ //seperate 2 nos into x and y based on right most set bit
if(arr[i]&right_bit){
x=x^arr[i];
}else{
y=y^arr[i];
}
}
ans.push_back(x);
ans.push_back(y);
return ans;
}
};
//{ Driver Code Starts.
int main(){
int T;
cin >> T;
while(T--)
{
int n;
cin >> n;
vector<int> v(2 * n + 2);
for(int i = 0; i < 2 * n + 2; i++)
cin >> v[i];
Solution ob;
vector<int > ans = ob.singleNumber(v);
for(auto i: ans)
cout << i << " ";
cout << "\n";
}
return 0;
}
// } Driver Code Ends