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-1];
		int sum =0;
		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();
		}
		for(int i=0;i<n;i++) {
			sum +=b[i];
		}
		for(int i=0; i<n-1; i++) {
			if((a[i]+1)==a[i+1]) {
				sum +=c[a[i]-1];
			}
		}
		System.out.println(sum);
	}

}