N=int(input())
A=list(map(int,input().split()))
B=list(map(int,input().split()))
C=list(map(int,input().split()))

satisfaction=0

for i in range(N):
    if  i>=1:
        if  A[i-1]+1==A[i]:
            satisfaction+=(C[A[i-1]-1]+B[A[i-1]-1])
 
        else:
            satisfaction+=B[A[i-1]-1]

print(satisfaction)