import java.util.Scanner;
public class Main{

	public static void main(String[] args) {
		Scanner stdIn = new Scanner(System.in);
		int n = stdIn.nextInt();
		int [] a = new int[n+1]; //それぞれの料理の配列
		int [] b = new int[n+1]; //それぞれの料理の満足度
		int [] c = new int[n-1]; //追加で得られる満足度
		
		
		for(int i = 0; i < n; i++) {
			a[i] = stdIn.nextInt();
		}
		
		for(int i = 0; i < n; i++) {
			b[i] = stdIn.nextInt();
		}
		
		for(int i = 0; i < c.length; i++) {
			c[i] = stdIn.nextInt();
		}
		
		int sum = 0;  //ここから満足度の合計を出す
		
		for(int i = 0; i < n; i++) {
			sum+=b[i];
			if(a[i+1]-a[i]==1) {
				sum+= c[a[i]-1];
			}
			
		}
		
		System.out.println(sum);
		
		
		
	}

}

/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