from collections import Counter
from sys import stdin


def main():
    input = lambda: stdin.readline()[:-1]
    N, X = map(int, input().split())
    A = [int(input()) for _ in [0] * N]

    cnt = Counter(A)
    ans = 0
    for a in A:
        n = X ^ a
        ans += cnt[n]
    print(ans // 2)


main()