XORX  xXor It!
Given an array of n integers and a number x. Your task is very simple. You have to find the subarray (length>0) whose xor is maximum with x. lets say the subarray as maxsubarray. You have to print the xor value of maxsubarray.
Input
First line of input consists of t test cases.
Second line of input contains two integers n and x.
Third line contains n space separated integers denoting the elements of array.
Output
First and only line of output is Xor value of maxsubarray.
Constraints
1<=t<=10
1<=n<=200000
1<=x<=2*10^9
1<=arr[i]<=2*10^9 where arr[i] is any integer of array.
Example
Input: 1 3 7 1 2 3 Output: 0
taking 1^2^3 is 0 when taken xor with 7 gives us the maximum xor value.
hide comments
princemishra:
20211126 10:09:49
INPUT


anonymous:
20200508 16:29:13
There are test cases which do not satisfy specified constraints:


kshubham02:
20191124 11:14:48
O(n*size_of_int) = O(n*32) is giving TLE! Is there a better solution?


vishal1510:
20181001 15:47:14
Can't be empty. 

pugachag:
20181001 15:28:30
In my AC submission I didn't consider empty subarrays, so you can safely assume that it can't be empty 

:D:
20181001 13:14:31
Can the subarray be empty?

Added by:  kumarvishalgupta 
Date:  20180930 
Time limit:  1.399s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All 