# your code goes here
n = int(input())
a = list(map(int, input().split()))
K = int(input())
p = [0] * n
p[0] = a[0]
for i in range(1, n):
p[i] = p[i - 1] ^ a[i]
max_l = 0
mp = {0: -1}
for j in range(n):
RHS = p[j] ^ K
if RHS in mp:
i = mp[RHS] + 1
length = j - i + 1
max_l = max(max_l, length)
if p[j] not in mp:
mp[p[j]] = j
print(max_l)
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