import java.util.*;

class Main{
  public static void main(String args[]){
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int[] a = new int[n];
    int[] b = new int[n];
    int[] c = new int[n-1];
    for(int i = 0; i < n; i++){
      a[i] = sc.nextInt();
    }
    for(int i = 0; i < n; i++){
      b[i] = sc.nextInt();
    }
    for(int i = 0; i < n-1; i++){
      c[i] = sc.nextInt();
    }
    int sum = 0;
    for(int i = 0; i < n-1; i++){
      sum += b[a[i]-1];
      if(a[i]+1 == a[i+1]){
        sum += c[a[i]-1];
      }
    }
    sum += b[a[n-1]-1];
    System.out.print(sum);
  }
}
