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.util.*;

public class NewYearBookReading500C
{
    public static void main(String[] args) 
    {
        // Set up scanner
        Scanner sc = new Scanner(System.in); 
        // System.out.println("Enter n");     // Number of books
        int n = sc.nextInt();
        // System.out.println("Enter m");    // Number of days reading
        int m = sc.nextInt();

        int[] w = new int[n+1];          // Array of book weights
        for (int i=1; i<=n; i++)
        {
            // System.out.println("Enter next weight");
            w[i] = sc.nextInt();
        }

        List<Integer> a = new LinkedList<Integer>();  // The current ordering on shelf
        Set<Integer> s = new HashSet<Integer>();          // The books we have seen
        int[] b = new int[m+1];                    // The books in the order they are read 
        for (int i=1; i<=m; i++)
        {
            // System.out.println("Enter next book to be read");
            b[i] = sc.nextInt();
            if (!s.contains(b[i]))
            {
                a.add(b[i]);
                s.add(b[i]);
            }
        }
        /*
        System.out.print("The initial ordering of the books is ");
        for (Integer i: a)
        {
            System.out.print(i + " ");
        }
        System.out.println();
        */

        //  Now loop over b and compute the answer (inefficiently at first...)
        int answer = 0;
        for (int i=1; i<=m; i++) 
        {
            int currentbook = b[i];
            // System.out.println("Looking in array a for " + currentbook);
            // Find where it is, and sum up weights above it for lifting
            int pos = 0;
            int weight = 0;
            while (a.get(pos) != currentbook)
            {
                weight = weight + w[a.get(pos)];
                pos++;
            }
            // System.out.println("Book " + currentbook + " found in slot " + pos);
            answer += weight;
            // System.out.println("Weight lifted is now " + answer);
            int temp = a.remove(pos);
            a.add(0, temp);
            /*
            System.out.print("The new ordering of the books is ");
            for (Integer j: a)
            {
                System.out.print(j + " ");
            }
            System.out.println();
            */

        }
        System.out.println(answer);
    }
}

        
         