Nw = int(input())

W = list(map(int, input().split()))
W.sort()

Nb = int(input())

B = list(map(int, input().split()))
B.sort()

from bisect import bisect_left
answ = 0
x = 1
y = 21
while True:
    if x:
        x = 0
        i = bisect_left(W, y)
        if i > 0:
            answ += 1
            y = W[i - 1]
        else:
            break
    else:
        x = 1
        i = bisect_left(B, y)
        if i > 0:
            answ += 1
            y = B[i - 1]
        else:
            break
ansb = 0
x = 0
y = 21
while True:
    if x:
        x = 0
        i = bisect_left(W, y)
        if i > 0:
            ansb += 1
            y = W[i - 1]
        else:
            break
    else:
        x = 1
        i = bisect_left(B, y)
        if i > 0:
            ansb += 1
            y = B[i - 1]
        else:
            break
print(max(ansb, answ))