import sys
n,b=map(int,input().split())
a=list(map(int,input().split()))
a.sort()
d=b.bit_length()
cnt=0
dp=[0]*(d+1)
for i in range(d):
	dp[i]=1<<i;
for i in a:
	tmp=i.bit_length()
	if tmp<d:
		cnt+=1
		b^=i
	if tmp==d:
		dp[d]=1
	if tmp>d:
		break
	for j in range(1,tmp):
		if (i>>j-1&1)==0:
			dp[tmp]|=dp[j]
	if tmp==d:
		if dp[d]>>(b^i).bit_length()&1:
			print(cnt+1)
			sys.exit()
print(cnt)