n = int(input())
a_list = list(map(int, input().split()))
b_list = list(map(int, input().split()))
c_list = list(map(int, input().split()))

score = 0

for val in b_list :
	score +=val
	
for val in range(n):
	if a_list[val+1] - a_list[val] == 1:
		score += c_list[val]
	else:
		pass

print(score)