N, X = map(int,input().split())

A = [0]*N
for i in range(N):
    A[i] = int(input())
    
cnt = {}

ans = 0
for a in A:
    if a^X in cnt:
        ans += cnt[a^X]
    if a not in cnt:
        cnt[a] = 1
    else:
        cnt[a] += 1
        
print(ans)