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