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

base = sum(B)
bonus = 0
for i, num in enumerate(A):
  if i+1 >= len(A):
    break
  if A[i+1] == A[i] + 1:
    bonus += C[i+1]

print(base + bonus)