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];
		int ans = 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++){
			ans += b[i];
		}

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