n, x = map(int,input().split())
A = [int(input()) for _ in range(n)]
cnt = {}
ans = 0
for a in A:
    rev_a = x ^ a
    if rev_a in cnt:
        ans += cnt[rev_a]
    if a in cnt:
        cnt[a] += 1
    else:
        cnt[a] = 1
print(ans)