N = int(input())
A = list(map(int, input().split()))+[0]     ###料理
B = list(map(int, input().split()))     ###満足度
C = list(map(int, input().split()))     ###連ちゃん

sum=sum(B)

for i in range(N):
    if A[i+1]-A[i]==1:
        sum+=C[i]

print(sum)

