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.*;
import java.io.*;
public class Main {
    public static void main(String args[]){
        //Scanner s= new Scanner(System.in);
         InputReader s= new InputReader(System.in);
         OutputStream outputStream= System.out;
         PrintWriter out= new PrintWriter(outputStream);
         int n=s.nextInt();
         int m=s.nextInt();
         int w[]=new int[n];
         int temp[]=new int[n+1];
         int b[]=new int[n];
         int read[]=new int[m];
         for(int i=0;i<n;i++){
             w[i]=s.nextInt();
         }
         int size=0;
         for(int i=0;i<m;i++){
             int x=s.nextInt();
             read[i]=x;
             if(temp[x]==0){
                 b[size]=x;
                 temp[x]=1;
                 size++;
             }
         }
         /*for(int i=0;i<size;i++){
             out.print(b[i]+" ");
         }*/
         int ans=0;
         for(int i=0;i<m;i++){
             for(int j=0;j<size;j++){
                 if(b[j]==read[i]){
                     int temp1=b[j];
                     for(int k=j-1;k>=0;k--){
                         
                         ans+=w[b[k]-1];
                         b[k+1]=b[k];
                         
                     }
                     b[0]=temp1;
                     break;
                 }
             }
         }
         out.println(ans);
         out.close();
    }
    
    static class InputReader {
        
        public BufferedReader reader;
        public StringTokenizer tokenizer;
 
        public InputReader( InputStream inputstream) {
          reader = new BufferedReader(new InputStreamReader(inputstream));
          tokenizer = null;
        }
        
        public String nextLine(){
            String fullLine=null;
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                  fullLine=reader.readLine();
                } catch (IOException e) {
                  throw new RuntimeException(e);
                }
                return fullLine;
              }
              return fullLine;
        }
        public String next() {
          while (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
              tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
              throw new RuntimeException(e);
            }
          }
          return tokenizer.nextToken();
        }
        public long nextLong() {
              return Long.parseLong(next());
            }
        public int nextInt() {
          return Integer.parseInt(next());
        }
      }
}
