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.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

public class CF21 {

	static BufferedReader br;

	public static void main(String[] args) throws IOException {
		br = new BufferedReader(new InputStreamReader(System.in));

		int[] arr = readIntArr();
		int n = arr[0];
		int x = arr[1];
		

		arr=readIntArr();
		br.close();
		Map<Integer,Integer>mp=new HashMap<Integer,Integer>();
		
		long cnt = 0;
		for (int i = 0; i < n; i++) {
			int xr = x ^ arr[i];
			
			Integer num=mp.get(xr);
			if(num!=null){
				cnt+=num;
			}
			Integer np=mp.get(arr[i]);
			if(np==null){
				np=1;
			}else{
				np++;
			}
			mp.put(arr[i], np);
			
		}
		System.out.println(cnt);

	}

	static public String readString() throws IOException {
		return br.readLine();

	}

	static public long readLong() throws IOException {
		return Long.parseLong(br.readLine());
	}

	static public int readInt() throws IOException {
		return Integer.parseInt(br.readLine());
	}

	static public int[] readIntArr() throws IOException {
		String[] str = br.readLine().split(" ");
		int arr[] = new int[str.length];
		for (int i = 0; i < arr.length; i++)
			arr[i] = Integer.parseInt(str[i]);
		return arr;
	}

	static public Integer[] readOIntArr() throws IOException {
		String[] str = br.readLine().split(" ");
		Integer arr[] = new Integer[str.length];
		for (int i = 0; i < arr.length; i++)
			arr[i] = new Integer(str[i]);
		return arr;
	}

	static public double[] readDoubleArr() throws IOException {
		String[] str = br.readLine().split(" ");
		double arr[] = new double[str.length];
		for (int i = 0; i < arr.length; i++)
			arr[i] = Double.parseDouble(str[i]);
		return arr;
	}

	static public Double[] readODoubleArr() throws IOException {
		String[] str = br.readLine().split(" ");
		Double arr[] = new Double[str.length];
		for (int i = 0; i < arr.length; i++)
			arr[i] = new Double(str[i]);
		return arr;
	}

	static public long[] readLongArr() throws IOException {
		String[] str = br.readLine().split(" ");
		long arr[] = new long[str.length];
		for (int i = 0; i < arr.length; i++)
			arr[i] = Long.parseLong(str[i]);
		return arr;
	}

	static public Long[] readOLongArr() throws IOException {
		String[] str = br.readLine().split(" ");
		Long arr[] = new Long[str.length];
		for (int i = 0; i < arr.length; i++)
			arr[i] = new Long(str[i]);
		return arr;
	}

	static public double readDouble() throws IOException {
		return Double.parseDouble(br.readLine());
	}
}
