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

d = 0
for i in b:
  d += i

for i in range(n):
  if i + 1 < n:
    if a[i] +1  == a[i+1]:
      d += c[i-1]
  
print(d)