from collections import Counter
n,x = map(int,input().split())
A = [int(input()) for i in range(n)]
C = Counter(A)
ans = 0

for a in A:
    x2 = a^x

    if x2 in C:
        if x2 == a:
            ans += C[a]-1
        else:
            ans += C[x2]
print(ans//2)