n = int(input())
a = [int(i) for i in input().split()]
b = [int(i) for i in input().split()]
c = [int(i) for i in input().split()]
# print(a)
# print(b)
# print(c)

prev = 0
s = sum(b)

for i in range(n-1):
    if a[i+1] == a[i] + 1:
        # print("match")
        s += c[i]

print(s)
