w=int(input())
W=set(map(int,input().split()))
b=int(input())
B=set(map(int,input().split()))
w,b=1,1
c=0
for x in W|B:
	if x in W and x in B: c+=1
	elif x in W and b: c+=1; w,b=1,0
	elif x in B and w: c+=1; w,b=0,1
print(c)