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.util.*;
import java.lang.*;
import java.io.*;
import java.math.*;
public class Main
{
@SuppressWarnings("unchecked") 
public static void main (String[] args) throws java.lang.Exception
{
//BufferedReader in=new BufferedReader(new FileReader(".\\mmk\\test\\A-small-attempt0.in"));
//PrintWriter out=new PrintWriter(".\\mmk\\test\\output.txt");
BufferedReader in=new BufferedReader(new InputStreamReader(System.in));
PrintWriter out=new PrintWriter(System.out);


int n,x,i,val,val1,comp,cnt;
long sum;


StringTokenizer st=new StringTokenizer(in.readLine());
n=Integer.parseInt(st.nextToken());
x=Integer.parseInt(st.nextToken());


int[] a=new int[n];
Hashtable<Integer,Integer> table=new Hashtable<Integer,Integer>();




st=new StringTokenizer(in.readLine());

for(i=0;i<n;i++)
{
a[i]=Integer.parseInt(st.nextToken());

if(!table.containsKey(a[i]))
    {
        table.put(a[i],0);
    }

val=table.get(a[i]);
table.put(a[i],val+1);

}




sum=0L;

for(i=0;i<n;i++)
{
comp=x^a[i];

if(table.containsKey(comp))
    {
    cnt=table.get(comp);

    if(a[i]==comp)
        cnt--;

    sum+=cnt;
    }

}



sum/=2;


out.println(sum);



out.flush();
out.close();
}
}