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)
if x != 0:
    for i in d:
        tmp = str(int(i) ^ x)
        # print(tmp)
        if tmp in d:
            ans += d[i] * d[tmp]
            d[tmp] = 0
else:
    for i in d:
        if d[i] >= 2:
            ans += int(d[i]*(d[i]-1)/2)
# print(d)
print(ans)