import java.util.Scanner;

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];

        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 res = b[a[0]];
        for(int i = 1;i<n;i++) {
            res += (b[a[i]]);
        if(a[i] - a[i-1] == 1)
            res+=c[a[i-1]];

        }
        System.out.println(res);


    }

}
