N = int(input())
A = [int(i) for i in input().split()]
B = [int(i) for i in input().split()]
C = [int(i) for i in input().split()]

counter = 0
for i in range(N):
    counter += B[i]
    if i != 0 and A[i] - 1 == A[i-1]:
        counter += C[i]
print(counter)
