import java.util.*;

class Main {
    final Scanner sc = new Scanner(System.in);

    public static void main(String[] args) {
        new Main().run();
    }

    private void run() {
        int n = sc.nextInt();
        int[] a = new int[n];
        int[] b = new int[n];
        int[] c = new int[n];

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

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

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

        int ans = 0;
        for (int i = 0; i < n; i++) {
            ans += b[a[i]];

            if (i > 0 && a[i] - a[i - 1] == 1) {
                ans += c[a[i - 1]];
            }
        }
        System.out.println(ans);
    }
}


/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