n,x = map(int, input().split())
a = [int(input()) for _ in range(n)]
# print(a)
a.sort()
ans = 0
d = {}
for i in a:
    tmp = str(i)
    if tmp not in d:
        d[tmp] = 1
    else:
        d[tmp] += 1
# print(d)
for i in d:
    tmp = str(int(i) ^ x)
    if tmp in d:
        ans += d[i] * d[tmp]
        d[tmp] = 0
print(ans)