n=int(input())
a=[int(x) for x in input().split(' ')]
b=[int(x) for x in input().split(' ')]
c=[int(x) for x in input().split(' ')]
satPoints=0
for i in range(n):
  if a[i]==a[i-1]+1 and i>0:
    satPoints+=c[a[i]-2]
  else:
    satPoints+=b[a[i]-1]