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.HashMap;
import java.util.Map;
import java.util.StringTokenizer;

/**
 * Created by akatsuki on 7/1/17.
 */
public class ArpasProblem {
//facct A^B=C==>A^C=B==>A,B,C must be unique
    public static void main(String[] args) throws IOException {
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        String s[]=br.readLine().split(" ");
        int N=Integer.parseInt(s[0]);
        int K=Integer.parseInt(s[1]);

        HashMap<Integer,Integer>hashMap=new HashMap<>();
        s=br.readLine().split(" ");
        for (int i = 0; i <N ; i++) {
           int num=Integer.parseInt(s[i]);
            if(hashMap.containsKey(num)){
                hashMap.put(num,hashMap.get(num)+1);
            }
            else hashMap.put(num,1);
        }

      long times=0;
        for (int key: hashMap.keySet()) {
            int xor = key ^ K;
            if (hashMap.containsKey(xor)) {
                if (xor != key) {
                 times += ((long)hashMap.get(key)) * ((long) hashMap.get(xor));
                } else {
                    times += ((long) hashMap.get(key)) * ((long) (hashMap.get(key) - 1));
                }
            }
        }
        OutputWriter out=new OutputWriter(System.out);
        out.println(times/2l);
        out.flush();
    }
}

class OutputWriter {
    private final PrintWriter writer;

    public OutputWriter(OutputStream outputStream) {
        writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
    }

    public OutputWriter(Writer writer) {
        this.writer = new PrintWriter(writer);
    }

    public void print(Object... objects) {
        for (int i = 0; i < objects.length; i++) {
            if (i != 0)
                writer.print(' ');
            writer.print(objects[i]);
        }
    }

    public void println(Object... objects) {
        print(objects);
        writer.println();
    }

    public void close() {
        writer.close();
    }

    public void flush() {
        writer.flush();
    }
}
