import sys
input = lambda: sys.stdin.readline().rstrip()
N, X = map(int, input().split())
D = {}
ans = 0
for _ in range(N):
    a = int(input())
    t = X ^ a
    if t in D:
        ans += D[t]
    
    if a in D:
        D[a] += 1
    else:
        D[a] = 1

print(ans)