A15579 | Comfortably Numb

You are given an array $a$ consisting of $n$ non-negative integers.

The numbness of a subarray $a_l, a_{l+1}, \ldots, a_r$ (for arbitrary $l \leq r$ ) is defined as $\max(a_l, a_{l+1}, \ldots, a_r) \oplus (a_l \oplus a_{l+1} \oplus \ldots \oplus a_r)$, where $\oplus$ denotes the [bitwise XOR operation](https://en.wikipedia.org/wiki/Bitwise_operation#XOR).

Find the maximum numbness over all subarrays.

Each test contains multiple test cases. The first line contains the number of test cases $t$ ( $1 \le t \le 1000$ ). The description of the test cases follows.

The first line of each test case contains a single integer $n$ ( $1 \leq n \leq 2 \cdot 10^5$ ).

The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ( $0 \leq a_i \leq 10^9$ ).

It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$ .

For each test case, print one integer — the maximum numbness over all subarrays of the given array.