N = int(input())
A = list(map(int, input().split()))
B = list(map(int, input().split()))
C = list(map(int, input().split()))
 
answer = 0
 
for i in range(N):
  answer = answer + B[i]
  
for i in range(N):
  if i != 0:
    if A[i] == A[i-1]+1:
      answer = answer + C[i-1]
    
print(answer)