There are some beautiful girls in Arpa’s land as mentioned before. 
Once Arpa came up with an obvious problem: 
Given an array and a number $x$, count the number of pairs of indices $i,j\ (1≤i<j≤n)$ such that $a_i \oplus a_j=x$, where $\oplus$ is bitwise $x$ oroperation (see notes for explanation). 

Immediately, Mehrdad discovered a terrible solution that nobody trusted. Now Arpa needs your help to implement the solution to that problem.


A bitwise xor takes two bit integers of equal length and performs the logical xor operation on each pair of corresponding bits. The result in each position is 1 if only the first bit is 1 or only the second bit is 1, but will be 0 if both are 0 or both are 1. You can read more about bitwisexoroperation here: https://en.wikipedia.org/wiki/Bitwise_operation#XOR.

First line contains two integers $n,x\ (1≤n≤10^5,\ 0≤x≤10^5)$− the number of elements in the array and the integer $x$.

Second line contains $n$ integers $a_1,a_2,...,a_n\ (1≤a_i≤10^5)$− the elements of the array.

Print a single integer: the answer to the problem.

1

there is only one pair of $i=1$ and $j=2.\ a_i \oplus a_j = 3 = x$ so the answer is 1.

2

the only two pairs are $i=3,j=4$ (since $2 \oplus 3 = 1$) and $i=1,j=5$ (since $5 \oplus 4 = 1$).