A straightforward question. Given an array of positive integers you have to
print the number of subarrays whose XOR is less than K.
Subarrays are defined as a sequence of continuous elements Ai, Ai+1, ..., Aj .
XOR of a subarray is defined as Ai^Ai+1^ ... ^Aj.
Symbol ^ is Exclusive Or. You can read more about it here:
http://en.wikipedia.org/wiki/Exclusive_or

Input Format:

First line contains T, the number of test cases. Each of the test case
consists of N and K in one line, followed by N space separated integers in
next line.

Output Format:

For each test case, print the required answer.

Constraints:

1 ≤ T ≤ 10
1 ≤ N ≤ 10^5
1 ≤ A[i] ≤ 10^5
1 ≤ K ≤ 10^6
Sum of N over all testcases will not exceed 10^5.

Sample Input:

1
5 2
4 1 3 2 7
Sample Output:

3
Explanation:

Only subarrays satisfying the conditions are [1],[1,3,2] and [3,2].

Problem Setter: Lalit Kundu

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