N = int(input())
A = map(int, input().split())
B = map(int, input().split())
C = map(int, input().split())
add_s = 0
for order in range(N-1):
  cur_f = A[order]
  nxt_f = A[order+1]
  add_s += C[order] if nxt_f == cur_f + 1 else 0
  
print(sum(B) + add_s)
