from collections import defaultdict


def main():
    N, X = map(int, input().split())

    ctr = 0
    xors = defaultdict(int)

    for _ in range(N):
        new_num = int(input())
        ctr += xors[new_num]
        xors[new_num ^ X] += 1

    print(ctr)


if __name__ == "__main__":
    main()