You are given an array \(A\) consisting of \(N\) integer values. Find an integer \(K\) such that the value of the following function is minimized:

• \(\sum_{i = 1}^{i = N} (A[i] \ XOR \ K)\) , \(XOR\) represents a bitwise XOR operation

If multiple such \(K\) exist, then print the minimum possible value of \(K\).

Input format

• The first line contains an integer \(T\) denoting the number of test cases. For each test case:
• The first line of each test case contains an integer \(N\).
• The second line of each test case contains \(N\) space-separated integers denoting array \(A\).

Output format

For each test case, print the value of \(K\) in a new line.

Constraints 

\(1 \le T \le 10 \\ 1 \le N \le 10^5 \\ 1 \le A[i] \le 10^{18}\)