XOR Pair Grouping Problem

You are given an array A of size N. Determine whether the array can be split into groups of pairs such that the XOR of each pair equals 0. Return true if it is possible, otherwise return false.

Input:

The first line contains a single integer 'T' representing the number of test cases. 
 For each test case, the input format is as follows: 
 - The first line contains an integer 'N'. 
 - The second line contains 'N' space-separated integers denoting the elements of array 'A'.

Output:

For each test case, print 'true' if the array can be divided into groups of pairs with XOR 0, otherwise print 'false'. 
 Each output should be on a new line.

Example:

Suppose the array is {1, 2, 2, 1}.

Possible pairs: {1, 1} and {2, 2}, both pairs satisfy XOR = 0, so output is true.

Constraints:

• 1 ≤ T ≤ 100
• 1 ≤ N ≤ 10^5
• 1 ≤ A[i] ≤ 10^5
• Time Limit: 1 sec

Note:

There is no requirement to print anything in your function. Just return the results for each test case.