n = int(input())
a = list(map(int,input().split()))
b = list(map(int,input().split()))
c = list(map(int,input().split()))
cnt = sum(b)
for i in range(n):
  if i<=n-2 and (a[i+1] - a[i] == 1):
    cnt += c[i]
print(cnt)