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 <image>, where <image> is bitwise xor operation (see notes for explanation).

<image>

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

Input

First line contains two integers n and x (1 ≤ n ≤ 105, 0 ≤ x ≤ 105) — the number of elements in the array and the integer x.

Second line contains n integers a1, a2, ..., an (1 ≤ ai ≤ 105) — the elements of the array.

Output

Print a single integer: the answer to the problem.

Examples

Input

2 3
1 2


Output

1

Input

6 1
5 1 2 3 4 1


Output

2

Note

In the first sample there is only one pair of i = 1 and j = 2. <image> so the answer is 1.

In the second sample the only two pairs are i = 3, j = 4 (since <image>) and i = 1, j = 5 (since <image>).

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 bitwise xor operation here: <https://en.wikipedia.org/wiki/Bitwise_operation#XOR>.
import java.io.*;
import java.util.*;
public class Hello{

	public static void main(String args[]) throws IOException{
	
	//BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    Scanner in = new Scanner(System.in);
    long n = in.nextLong();
    long x = in.nextLong();
    long count = 0;
    long arr[] = new long[10000000];
    Arrays.fill(arr , 0);
    for (long i = 0; i<n ;i++ ) {
        //arr[i] = in.nextlong();
        long a = in.nextLong();
        count += arr[(int)(x^a)];
        arr[(int)a]++;

    }
    /*for (long i = 0; i<n ; i++ ) {
        for (long j = i+1; j<n ; j++ ) {
            if ((arr[i] ^ arr[j]) == x ) {

                count++;
            }
        }
        
    }*/
    System.out.println(count);

    
}
}


