import java.util.*;
class Main
{
  public static void main(String Args[])
  {
    Scanner in = new Scanner(System.in);
    int n = in.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] = in.nextInt();
    for(int i = 0;i<n;i++)
      B[i] = in.nextInt();
    for(int i = 0;i<n-1;i++)
      C[i] = in.nextInt();
    int sum = 0;
    int last = 0;
    for(int i = 0;i<n;i++)
    {
      int a = A[i]-1;
      if(i!=0)
      {
        sum += B[a];
        if(a-last==1)
          sum+= C[last];
        last = a;
      }
      else{
        sum += B[a];
        last = a;
      }
    }
     System.out.println(sum);
  }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz