N = int(input())
li_a = list(map(int, input().split()))
li_b = list(map(int, input().split()))
li_c = list(map(int, input().split()))
C = 0
for i in range(N-1):
  if li_a[i] == li_a[i+1] - 1:
    C += li_c[i]
B = sum(li_b)
print(B+C)