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>.
'''
@sksshivam007 - Template 1.0
'''
import sys, re, math
from collections import deque, defaultdict, Counter, OrderedDict
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from queue import Queue
from heapq import heappush, heappop, heapify, nlargest, nsmallest
def STR(): return list(input())
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(): return list(map(int, input().split()))
def list2d(a, b, c): return [[c] * b for i in range(a)]
def sortListWithIndex(listOfTuples, idx):   return (sorted(listOfTuples, key=lambda x: x[idx]))
def sortDictWithVal(passedDic):
    temp = sorted(passedDic.items(), key=lambda kv: (kv[1], kv[0]))[::-1]
    toret = {}
    for tup in temp:
        toret[tup[0]] = tup[1]
    return toret
def sortDictWithKey(passedDic):
    return dict(OrderedDict(sorted(passedDic.items())))

INF = float('inf')
mod = 10 ** 9 + 7


def nCr(n, r):
    return (fact(n) / (fact(r)
                       * fact(n - r)))


# Returns factorial of n
def fact(n):
    res = 1

    for i in range(2, n + 1):
        res = res * i

    return res

n,x = MAP()

occ = defaultdict(int)

a = LIST()

for el in a:
    occ[el]+=1

if(x!=0):
    ans = 0
    for el in a:
        ans+=occ[el^x]
    print(ans//2)
else:
    ans = 0
    for key in occ:
        if(occ[key]>1):
            ans+=occ[key]*(occ[key]-1)//2

    print(int(ans))