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.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;


public class Main {

    public static void main(String[] args) throws Exception {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        InputReader inputReader = new InputReader(in);
        PrintWriter out = new PrintWriter(System.out);

        int n = inputReader.getNextInt();
        int x = inputReader.getNextInt();

        Map<Integer, Integer> occurences = new HashMap<>();
        long sol = 0;

        for(int i = 0; i < n; i++) {
            int y = inputReader.getNextInt();
            sol = sol + occurences.getOrDefault(x ^ y, 0);
            occurences.put(y, occurences.getOrDefault(y, 0) + 1);
        }

        out.println(sol);

        in.close();
        out.close();
    }

    public static class InputReader {

        static final String SEPARATOR = " ";

        String[] split;
        int head = 0;
        BufferedReader in;

        public InputReader(BufferedReader in) {
            this.in = in;
        }

        private void fillBuffer() throws IOException {
            if(split == null || head >= split.length) {
                head = 0;
                split = in.readLine().split(SEPARATOR);
            }
        }

        public String getNextToken() throws IOException {
            fillBuffer();
            return split[head++];

        }

        public int getNextInt() throws IOException {
            return Integer.parseInt(getNextToken());
        }

        public long getNextLong() throws IOException {
            return Long.parseLong(getNextToken());
        }
    }

}