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

/*
 *
 * @author Mukesh Singh
 *
 */

/* Finding_the_Minimum_Window_in_S_which_Contains_All_Elements_from_T */

import java.io.*;
import java.util.*;
import java.text.DecimalFormat;
@SuppressWarnings("unchecked")
public class AB
{	
	int ar[] ;
	//solve test cases
	void solve() throws Exception 
	{
		int n = in.nextInt();
		int m = in.nextInt();
		ar = new int[n+1];
		for( int i = 1 ; i <= n ; i++ )
			ar[i] = in.nextInt();
		int br[] = new int[m+1];
		for(int i = 0 ; i < m ; i++ )
			br[i] = in.nextInt();
		int st[] = new int[n+1];
		int cur = -1 ;
		for(int i = 0 ; i < m ; i++ )
		{
			boolean found = false ;
			for(int j= 0 ;j <= cur ; j ++ )
			{
				if(st[j]==br[i])
				{
					found = true ;
					break ;
				}
			}
			if(!found)
			{
				cur++ ;
				st[cur] = br[i] ;
			}
		}
		long ans = 0 ;
		for( int i = 0 ;i  < m ; i ++ )
		{
			int read = br[i] ;
			int pos = 0; 
			while(read != st[pos])
			{
				ans = ans + ar[read] ;
				pos++ ;
			}
			//rearrange
			int temp = st[pos] ;
			while(pos > 0 )
			{
				st[pos] = st[pos-1] ;
				pos -- ; 
			}
			st[0] = temp ;
		}
		System.out.println(ans);
	}
	//@ main function
	public static void main(String[] args) throws Exception 
	{
		new AB();
	}
	
	InputReader in;
	PrintStream out ;
	DecimalFormat df ;
	AB() 
	{
		try 
		{
			File defaultInput = new File("file.in");
			if (defaultInput.exists()) 
				in = new InputReader("file.in");
			else 
				in = new InputReader();
			defaultInput = new File("file.out");
			if (defaultInput.exists()) 
				out = new PrintStream(new FileOutputStream("file.out"));
			else
				out = new PrintStream(System.out);
			df = new DecimalFormat("######0.00");
			solve();
			out.close();
		} 
		catch (Exception e) 
		{
			e.printStackTrace();
			System.exit(261);
		}
	}
	
	class InputReader {
		BufferedReader reader;
		StringTokenizer tokenizer;
		
		InputReader() {
			reader = new BufferedReader(new InputStreamReader(System.in));
		}
		
		InputReader(String fileName) throws FileNotFoundException {
			reader = new BufferedReader(new FileReader(new File(fileName)));
		}
		
		String readLine() throws IOException {
			return reader.readLine();
		}
		
		String nextToken() throws IOException {
			while (tokenizer == null || !tokenizer.hasMoreTokens())
				tokenizer = new StringTokenizer(readLine());
			return tokenizer.nextToken();
		}
		
		boolean hasMoreTokens() throws IOException {
			while (tokenizer == null || !tokenizer.hasMoreTokens()) {
				String s = readLine();
				if (s == null)
					return false;
				tokenizer = new StringTokenizer(s);
			}
			return true;
		}
		
		int nextInt() throws NumberFormatException, IOException {
			return Integer.parseInt(nextToken());
		}
		
		long nextLong() throws NumberFormatException, IOException {
			return Long.parseLong(nextToken());
		}
		
		double nextDouble() throws NumberFormatException, IOException {
			return Double.parseDouble(nextToken());
		}
	}
}
