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.InputStreamReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Map;
import java.util.HashMap;
import java.util.StringTokenizer;

public class B {
	public static void main(String[] args) {
		FastScanner fs=new FastScanner();
		PrintWriter pw=new PrintWriter(System.out);

		int n=fs.nextInt();
		int x=fs.nextInt();
		int[] as=new int[n];
		int m=-1;
		for (int i=0; i<n; ++i) {
			as[i]=fs.nextInt();
			m=(m<as[i])?as[i]:m;
		}
		long c=0;
		int[] ts=new int[m+1];
		for (int i=0; i<n; ++i) {
			try {
				c+=ts[as[i]^x];
			} catch (ArrayIndexOutOfBoundsException e) {
				continue;
			} finally {
				++ts[as[i]];
			}
		}

		pw.println(c);

		pw.close();
	}

	static class FastScanner {
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st=new StringTokenizer("");

		String next() {
			while (!st.hasMoreTokens()) {
				try {
					st=new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt() {
			return Integer.parseInt(next());
		}
	}
}
