def main():
    n,x = map(int,input().split())
    a = [int(input()) for i in range(n)]
    lim = max(a)
    b = [0 for i in range(lim + 1)]
    for i in range(n):
       b[a[i] ^ x] += 1
    cnt = 0
    for i in range(n):
        cnt += b[a[i]]

    print(cnt // 2)
main()