Nobita wants to impress Shizuka by guessing her lucky number.

Shizuka gave Nobita a sorted list of ‘N’ numbers such that every number occurred twice in the list except Shizuka’s lucky number which appears only once.

Nobita asked Doraemon to help him but Doraemon doesn’t have a gadget that can find Shizuka’s lucky number.

So, Doraemon called you to find Shizuka’s lucky number. The fate of Nobita lies in your hand.

Note :

1. Shizuka’s lucky number will surely be present.
2. There will only be a single lucky number.

Input Format :

The first line of input contains an integer 'T' representing the number of test cases. Then the test cases follow.

The first line of each test case contains a single integer ‘N’, representing the total number of elements present in Shizuka’s list.

The next line contains ‘N’ single-spaced elements, representing the elements of Shizuka’s list

Output Format :

For each test case, print an integer denoting the lucky number of Shizuka.

The output for each test case will be printed in a separate line.    

Constraints :

1 <= T <= 5
1 <= N <= 10^5
0 <= data <= 10^9

Where ‘data’ is the value of elements of Shizuka’s list. 

Time Limit: 1 sec

Note :

You do not need to print anything, it has already been taken care of. Just implement the given function.