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.io.*;
public class xorpair
{
    static class InputReader {
        private InputStream stream;
        private byte[] inbuf = new byte[1024];
        private int start= 0;
        private int end = 0;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        private int readByte() {
            if (start == -1) throw new UnknownError();
            if (end >= start) {
                end= 0;
                try {
                    start= stream.read(inbuf);
                } catch (IOException e) {
                    throw new UnknownError();
                }
                if (start<= 0) return -1;
            }
            return inbuf[end++];
        }

        private boolean isSpaceChar(int c) {
            return !(c >= 33 && c <= 126);
        }

        private int skip() {
            int b;
            while ((b = readByte()) != -1 && isSpaceChar(b)) ;
            return b;
        }

        public String next() {
            int b = skip();
            StringBuilder sb = new StringBuilder();
            while (!(isSpaceChar(b))) { // when nextLine, (isSpaceChar(b) && b != ' ')
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }

        public int nextInt() {
            int num = 0, b;
            boolean minus = false;
            while ((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')) ;
            if (b == '-') {
                minus = true;
                b = readByte();
            }

            while (true) {
                if (b >= '0' && b <= '9') {
                    num = num * 10 + (b - '0');
                } else {
                    return minus ? -num : num;
                }
                b = readByte();
            }
        }

        public long nextLong() {
            long num = 0;
            int b;
            boolean minus = false;
            while ((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')) ;
            if (b == '-') {
                minus = true;
                b = readByte();
            }

            while (true) {
                if (b >= '0' && b <= '9') {
                    num = num * 10 + (b - '0');
                } else {
                    return minus ? -num : num;
                }
                b = readByte();
            }
        }
    }
    static void shuffle(int a[])
    {
        List<Integer> l=new ArrayList<>();
        for(int i=0;i<a.length;i++)
            l.add(a[i]);
        Collections.shuffle(l);
        for(int i=0;i<a.length;i++)
            a[i]=l.get(i);
    }

    public static void main(String args[])
    {
        InputReader sc=new InputReader(System.in);
        int n,k,i;
        n=sc.nextInt();
        k=sc.nextInt();
        int a[]=new int[n];
        int b[]=new int[1000009];
        int c[]=new int[1000009];
        long count=0;
        for( i=0;i<n;i++)
        {
            a[i]=sc.nextInt();
            b[a[i]]+=1;
        }
        for(i=0;i<n;i++)
        {
            if(b[a[i]^k]!=0 && c[a[i]^k]==0)
            {
                c[a[i]]=1;
                c[a[i]^k]=1;
                if(a[i]!=(a[i]^k))
                    count=count+((long)b[a[i]]*b[a[i]^k]);
                else
                {
                    count=count+((long)b[a[i]]*(b[a[i]]-1))/2;
                }
            }
        }
        System.out.println(count);
    }
}