NW = int(input())
W = list(map(int,input().split()))
NB = int(input())
B = list(map(int,input().split()))
W.sort()
B.sort()
WB = [W+[0],B+[0]]
NWB = [NW,NB]

def solve(x):
    tmp = []
    wb = [0,0]
    turn = x
    now = 0
    b = 0
    cnt = 0
    while wb[turn] < NWB[turn]:
        while wb[turn] < NWB[turn] and now >= WB[turn][wb[turn]]:
            wb[turn] += 1
        if WB[turn][wb[turn]] == 0:
            #print(tmp,cnt)
            return cnt
        now = WB[turn][wb[turn]]
        tmp.append((turn,now))
        wb[turn] += 1
        cnt += 1
        turn ^= 1
    #print(tmp,cnt)
    return cnt

ans = 0
for i in range(2):
    ans = max(ans,solve(i))
print(ans)