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 C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

int main(void){
  char str1[5],str2[100],str3[100],str4[100];
  int N,a[20],b[20],c[20],i,sum;
  
  fgets(str1,sizeof(str1),stdin);
  fgets(str2,sizeof(str2),stdin);
  fgets(str3,sizeof(str3),stdin);
  fgets(str4,sizeof(str4),stdin);
  
  N=atoi(str1);
  a[0]=atoi(strtok(str2," "));
  for(i=1;i<N;i++){
    a[i]=atoi(strtok(NULL," "));
  }
  b[0]=atoi(strtok(str3," "));
  for(i=1;i<N;i++){
    b[i]=atoi(strtok(NULL," "));
  }
  c[0]=atoi(strtok(str4," "));
  for(i=1;i<N-1;i++){
    c[i]=atoi(strtok(NULL," "));
  }
  
  sum=b[a[0]];
  for(i=1;i<N;i++){
    sum+=b[a[i]];
    if(a[i]==a[i-1]+1){
      sum+=c[a[i-1]];
    }
  }
  
  printf("%d\n",sum);
  return 0;
}