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.*;
import java.text.DecimalFormat;
import java.util.*;

public class Main {

	static BufferedReader br = new BufferedReader(new InputStreamReader(
			System.in));
	static PrintWriter out = new PrintWriter(new BufferedOutputStream(
			System.out));
	static StringTokenizer st = new StringTokenizer("");

	public static String next() {
		try	{
		while (!st.hasMoreTokens()) {
			String s = br.readLine();
			if (s == null)
				return null;
			st = new StringTokenizer(s);
		}
		return st.nextToken();
		}	catch(Exception e)	{
			return	null;
		}
	}

	public static void main(String[] args) {

	//	int CASES = Integer.parseInt( next() );

		int N = Integer.parseInt( next() );
		int M = Integer.parseInt( next() );
		int [] v = new int [N];
		Integer [] s = new Integer [N];
		for (int i = 0; i < N; i++)	{
			v[i] = Integer.parseInt( next() );
			s[i] = i;
		}
		
		int [] get = new int [M];
		for (int i = 0; i < M; i++)
			get[i] = Integer.parseInt( next() ) - 1;
		
		final int [] first = new int [N];
		final int [] cnt = new int [N];
		for (int i = M - 1; i >= 0; i--)	{
			first[ get[i] ] = i;
			cnt[ get[i] ]++;
		}
		
		Arrays.sort( s, new Comparator<Integer>() {
			
			public int compare(Integer a, Integer b)	{
				if	( cnt[a] != cnt[b] )
					return	cnt[b] - cnt[a];
				return	first[a] - first[b];
			}
		});
		
		LinkedList<Integer> list = new LinkedList<Integer>();
		for (int i = 0; i < N; i++)	{
			list.add( s[i] );
		}
		
		//
		int total = 0;
		for (int x : get)	{
			for (int k = 0, val = list.get(0); k < N; k++, val = list.get(k))	{
				if	( val == x )	{
					list.remove(k);
					list.addFirst(x);
					break;
				}
				total += v[val];
			}
			
		}
		out.println(total);
		
		
		//
		out.flush();
		out.close();
	}
	
	
}










