def solution(n, m, arr1, arr2):
    dp = [0 for _ in range(m+1)]
    res_max = 0
    for i in range(n-1, -1, -1):
        for j in range(m):
            if arr1[i] == arr2[j]:
                dp[j] = dp[j+1] + 1
            else:
                dp[j] = 0
            res_max = max(res_max, dp[j])
    return res_max


n = int(input())
arr1 = list(map(int, input().split()))
m = int(input())
arr2 = list(map(int, input().split()))
print(solution(n, m, arr1, arr2))