from bisect import bisect_right
NW = int(input())
W = list(map(int, input().split()))
NB = int(input())
B = list(map(int, input().split()))

W.sort()
B.sort()
WB = [W, B]

ans = 0
for i in range(2):
    lim = min(NW, NB)*2 + (NW != NB)
    blk = 0
    h = 0
    for j in range(lim):
        wb = (i + j) % 2
        p = bisect_right(WB[wb], blk)
        if p >= len(WB[wb]):
            break
        h += 1
        blk = WB[wb][p]
    ans = max(ans, h)
print(ans)