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.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.InputMismatchException;
import java.io.IOException;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        TaskB solver = new TaskB();
        solver.solve(1, in, out);
        out.close();
    }

    static class TaskB {
        public void solve(int testNumber, InputReader in, PrintWriter out) {
            int n = in.nextInt();
            int x = in.nextInt();

            int a[] = new int[n];
            int b[] = new int[n];
            for (int i = 0; i < n; ++i) {
                a[i] = in.nextInt();
                b[i] = a[i];
            }
            Arrays.sort(b);
            long re = 0;
            for (int i = 0; i < n; ++i) {
                int y = x ^ a[i];
                int s = MathUtils.lowerBound(b, y);
                int e = MathUtils.upperBound(b, y);
                re += e - s;
                if (y == a[i]) re--;
            }
            out.println(re / 2);

        }

    }

    static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;

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

        public int read() {
            if (numChars == -1)
                throw new InputMismatchException();
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (numChars <= 0)
                    return -1;
            }
            return buf[curChar++];
        }

        public int nextInt() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            int res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public static boolean isSpaceChar(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

    }

    static class MathUtils {
        public static int lowerBound(int a[], int first, int last, int key) {
            int count = last - first, step;
            int it;
            while (count > 0) {
                it = first;
                step = count / 2;
                it += step;
                if (a[it] < key) {
                    first = ++it;
                    count -= step + 1;
                } else
                    count = step;
            }
            return first;
        }

        public static int lowerBound(int a[], int key) {
            return lowerBound(a, 0, a.length, key);
        }

        public static int upperBound(int[] a, int first, int last, int key) {
            int it;
            int count = last - first, step;

            while (count > 0) {
                it = first;
                step = count / 2;
                it += step;
                int _cmp = Integer.compare(key, a[it]);
                //if (!(val<*it))
                if (!(_cmp < 0)) {
                    first = ++it;
                    count -= step + 1;
                } else count = step;
            }
            return first;
        }

        public static int upperBound(int[] a, int key) {
            return upperBound(a, 0, a.length, key);
        }

    }
}

