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

    print(cnt // 2)
main()