N,X = map(int, input().split())
A = [int(input()) for _ in range(N)]

ans = 0
dic = {}
for a in A:
    if a in dic:
        dic[a] += 1
    else:
        dic[a] = 1

for a in A:
    b = a^X
    if b in dic:
        ans += dic[b]
print(ans//2)