N = input()
array_A = list(map(int, input().split()))
array_B = list(map(int, input().split()))
array_C = list(map(int, input().split()))

#print(N)
#print(array_A)
#print(array_B)
#print(array_C)

bonus = []
for i in range(len(array_A)-1):
  if array_A[i] + 1 == array_A[i+1]:
    bonus += [i]

#print(bonus)

bonus_point = 0
for i in range(len(bonus)):
  bonus_point += array_C[i]

#print(bonus_point)  
score = sum(array_B) + bonus_point
print(score)