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)]
    d = {}
    for i in range(n):
       d.setdefault(a[i] ^ x,0)
       d[a[i] ^ x] += 1

    cnt = 0
    for i in range(n):
        d.setdefault(a[i],0)
        cnt += d[a[i]]

    print(cnt // 2)
main()