50 50
75 71 23 37 28 23 69 75 5 62 3 11 96 100 13 50 57 51 8 90 4 6 84 27 11 89 95 81 10 62 48 52 69 87 97 95 30 74 21 42 36 64 31 80 81 50 56 53 33 99
26 30 5 33 35 29 6 15 36 17 32 16 14 1 29 34 22 40 12 42 38 48 39 50 13 47 18 43 10 8 49 45 11 31 21 37 46 28 20 41 2 7 9 24 27 23 3 44 15 14
 10 10
61 59 97 16 2 94 57 48 91 93
2 8 6 5 3 1 3 4 9 10
 2 1
1 2
1
 3 3
10 20 30
1 2 3
 50 60
86 57 45 93 17 12 40 10 47 80 18 80 3 9 6 55 13 99 5 76 4 70 100 55 27 91 71 3 65 93 41 74 80 56 90 50 58 13 71 9 47 52 26 73 72 21 15 81 88 28
40 32 5 16 49 23 3 17 14 10 1 15 1 21 28 22 13 45 12 25 44 48 46 32 36 43 11 8 49 7 7 35 10 14 39 4 42 10 30 27 1 17 31 15 8 41 44 33 25 26 19 18 29 37 50 6 36 38 47 9
 2 7
20 30
1 1 1 2 2 2 2
 2 2
10 12
2 1
 5 1
16 87 36 16 81
3
 2 3
20 30
1 1 1
 2 10
39 26
1 1 2 2 2 2 2 2 1 2

63929
 2137
 0
 40
 62514
 20
 12
 0
 0
 104

import java.io.BufferedInputStream;
import java.util.*;

/**
 * Created by admin on 2016/7/22.
 */
public class main1 {

    public static void main(String[] args){
        Scanner scanner = new Scanner(new BufferedInputStream(System.in));
        int bookNum = scanner.nextInt();
        int dayNum = scanner.nextInt();
        int[] books = new int[bookNum];
        int[] orders = new int[dayNum];


        for(int i = 0 ; i < bookNum ; i ++){
            books[i] = scanner.nextInt();
        }

        for(int i = 0 ; i < dayNum; i++){
            orders[i] = scanner.nextInt();
        }

        Set<Integer> tmpSet = new HashSet<>();
        ArrayList<Integer> tmpArray = new ArrayList<>();
        for(int i = 0; i < dayNum; i++){
            if(tmpSet.add(orders[i])){
                tmpArray.add(orders[i]);
            }
        }

        int totalSize = 0;
        for(int i = 0 ; i < orders.length; i++){
            totalSize = totalSize + cal(books, tmpArray, orders[i]);
        }
        System.out.println(totalSize);
    }

    public static int cal(int[] book, ArrayList<Integer> order, int bookOrder){
        int realbookOrder = 0;
        int totalSize = 0;
        for(int i = 0 ; i < order.size(); i++){
            if(order.get(i) == bookOrder){
                realbookOrder = i;
                break;
            }

            totalSize = totalSize + book[order.get(i) - 1];
        }
        order.remove(realbookOrder);
        order.add(0, bookOrder);
        return totalSize;
    }
}

  		    		 		 	 	   	    	 			