import java.util.*;

public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		int s = 0;
		int n = sc.nextInt();
		int[] a = new int[n], b = new int[n], c = new int[n-1];

		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++) {
			s += b[a[i] - 1];
			if(i != 0 && a[i - 1] + 1 == a[i]) s += c[a[i] - 2];
		}

		System.out.println(s);
	}
}
/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