import java.util.*;

public 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];

    int result = 0;

    for(int i = 0; i < N; i++) {
      A[i] = sc.nextInt();
    }

    for(int i = 0; i < N; i++) {
      B[i] = sc.nextInt();
      result += B[i];
    }

    for(int i = 0; i < N - 1; i++) {
      C[i] = sc.nextInt();  
    }

    sc.close();

    for(int i = 0; i < N - 1; i++) {
      if (A[i] + 1 == A[i + 1]){
        result += C[A[i] - 1];
      }
    }

    System.out.println(result);

  }

}
