N = int(input())

As = [int(i) for i in input().split()]
Bs = [int(i) for i in input().split()]
Cs = [int(i) for i in input().split()]

# c_counter = 0
value = 0
previous_plate_index = -1

for i in range(N):    
    plate_index = As[i] - 1
    value += Bs[plate_index]
    if plate_index == previous_plate_index + 1:
            value += Cs[previous_plate_index]
    previous_plate_index = plate_index

print(value)