n=int(input())
lista=list(map(int,input().split()))
listb=list(map(int,input().split()))
listc=list(map(int,input().split()))
list=[]
for i in range(n):
  if lista[i]==lista[i-1]+1:
    list.append(lista[i-1])
vonus=0
for x in list:
  vonus+=listc[x-1]
print(sum(listb)+vonus)