Problem:
Score : 200 points

Problem Statement

Takahashi went to an all-you-can-eat buffet with N kinds of dishes and ate all of them (Dish 1, Dish 2, \ldots, Dish N) once.

The i-th dish (1 \leq i \leq N) he ate was Dish A_i.

When he eats Dish i (1 \leq i \leq N), he gains B_i satisfaction points.

Additionally, when he eats Dish i+1 just after eating Dish i (1 \leq i \leq N - 1), he gains C_i more satisfaction points.

Find the sum of the satisfaction points he gained.

Constraints

All values in input are integers.

2 \leq N \leq 20

1 \leq A_i \leq N

A_1, A_2, ..., A_N are all different.

1 \leq B_i \leq 50

1 \leq C_i \leq 50

Input

Input is given from Standard Input in the following format:

N
A_1 A_2 ... A_N
B_1 B_2 ... B_N
C_1 C_2 ... C_{N-1}

Output

Print the sum of the satisfaction points Takahashi gained, as an integer.

Sample Input 1

3
3 1 2
2 5 4
3 6

Sample Output 1

14

Takahashi gained 14 satisfaction points in total, as follows:

First, he ate Dish 3 and gained 4 satisfaction points.

Next, he ate Dish 1 and gained 2 satisfaction points.

Lastly, he ate Dish 2 and gained 5 + 3 = 8 satisfaction points.

Sample Input 2

4
2 3 4 1
13 5 8 24
45 9 15

Sample Output 2

74

Sample Input 3

2
1 2
50 50
50

Sample Output 3

150

Solution in PHP7 (7.0.15) (judge verdict: Accepted)

<?php
// From https://qiita.com/yoshikyoto/items/6924478283dbdd549e4b
class Scanner {
    private $arr = [];
    private $count = 0;
    private $pointer = 0;
    public function next() {
        if($this->pointer >= $this->count) {
            $str = trim(fgets(STDIN));
            $this->arr = explode(' ', $str);
            $this->count = count($this->arr);
            $this->pointer = 0;
        }
        $result = $this->arr[$this->pointer];
        $this->pointer++;
        return $result;
    }
    public function hasNext() {
        return $this->pointer < $this->count;
    }
    public function nextInt() {
        return (int)$this->next();
    }
    public function nextDouble() {
        return (double)$this->next();
    }
}
// From https://qiita.com/yoshikyoto/items/6924478283dbdd549e4b
list($N)=sscanf(trim(fgets(STDIN)),"%d");
$sc = new Scanner();
$A=array();
for($i=0;$i<$N;$i++){
    $A[$i] = $sc->nextInt();
}
$sc = new Scanner();
$B=array();
for($i=0;$i<$N;$i++){
    $B[$i] = $sc->nextInt();
}
$sc = new Scanner();
$C=array();
for($i=0;$i<$N-1;$i++){
    $C[$i] = $sc->nextInt();
}
$sum=0;
$pre=11111111;
for($i=0;$i<$N;$i++){
    $sum += $B[$A[$i]-1];
    if($pre == $A[$i]-1-1){
        $sum += $C[$pre];
    }
    $pre = $A[$i]-1;
}
printf($sum);
//