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.Map;
import java.util.Scanner;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class ProblemB {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        String[] firstLine = sc.nextLine().split(" ");
//        int size = Integer.valueOf(firstLine[1]);
        int intComparator = Integer.valueOf(firstLine[1]);

        String[] integersToCompare = sc.nextLine().split(" ");

//        String[] b = new String[100000];
//        for (int i = 0; i < 100000; i++) {
//            b[i] = "" + i;
//        }

        long method = m2(intComparator, integersToCompare);
//        int method = m2(intComparator, b);

        System.out.println(method);
    }

    static long m2(int intComparator, String[] integersToCompare) {
        Map<String, Long> occurrences = Stream
                .of(integersToCompare)
                .collect(Collectors.groupingBy(s -> s, Collectors.counting()));

        Long reduce = Stream.of(integersToCompare)
                            .map(s -> {
                                final int integer = Integer.valueOf(s);
                                return new Val(integer, integer ^ intComparator);
                            })
                            .filter(l -> occurrences.containsKey("" + l.corr))
                            .map(val -> {
                                final int corr = val.corr;
                                if (corr == val.val) {
                                    return occurrences.get("" + corr) - 1;
                                }
                                return occurrences.get("" + corr);
                            })
                            .reduce(Long.valueOf("0"), (a, b) -> a + b);

        return Long.valueOf(reduce.toString()) / 2;
    }

    private static class Val {
        private final int val;
        private final int corr;


        private Val(int val, int corr) {
            this.val = val;
            this.corr = corr;
        }
    }
}
