def solve(A,pos_a,B,pos_b):
	ans = 0
	tmp = 21
	while 1:
		while A[pos_a] >= tmp:
			pos_a -= 1
			if pos_a < 0:
				return ans
		ans += 1
		tmp = A[pos_a]
		while B[pos_b] >= tmp:
			pos_b -= 1
			if pos_b < 0:
				return ans
		ans += 1
		tmp = B[pos_b]

Nw = input()
W = map(int,raw_input().split())
Nb = input()
B = map(int,raw_input().split())
W.sort()
B.sort()
print max(solve(W,Nw-1,B,Nb-1),solve(B,Nb-1,W,Nw-1))