import java.util.*;
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[a[i] - 1];
			if(i < n-1){
				if(a[i+1] - a[i] == 1){
				sum += c[a[i]-1];
			}
		}}
	
		System.out.println(sum);
	}
}