import java.util.Scanner;

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