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.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;

public class Main{

	public static int[] readInts(String cad) {
		String read[] = cad.split(" ");
		int res[] = new int[read.length];
		for (int i = 0; i < read.length; i++) {
			res[i] = Integer.parseInt(read[i]);
		}
		return res;
	}

	public static long[] readLongs(String cad) {
		String read[] = cad.split(" ");
		long res[] = new long[read.length];
		for (int i = 0; i < read.length; i++) {
			res[i] = Long.parseLong(read[i]);
		}
		return res;
	}

	static void printArrayInt(int[] array) {
		if (array == null || array.length == 0)
			return;
		for (int i = 0; i < array.length; i++) {
			if (i > 0)
				System.out.print(" ");
			System.out.print(array[i]);
		}
		System.out.println();
	}

	static void printMatrixInt(int[][] array) {
		if (array == null || array.length == 0)
			return;
		for (int i = 0; i < array.length; i++) {
			for (int j = 0; j < array[0].length; j++) {
				if (j > 0)
					System.out.print(" ");
				System.out.print(array[i][j]);
			}
			System.out.println();
		}

	}

	public static int max(int arr[]) {
		int max = arr[0];
		for (int i = 1; i < arr.length; i++) {
			max = Math.max(max, arr[i]);
		}
		return max;
	}

	public static int min(int arr[]) {
		int min = arr[0];
		for (int i = 1; i < arr.length; i++) {
			min = Math.min(min, arr[i]);
		}
		return min;
	}

	public static int w[], b[];
	public static Node v[];

	public static class Node {
		int book;
		int w;

		public Node(int index, int w) {
			this.book = index;
			this.w = w;
		}

		@Override
		public String toString() {
			return book + " " + w;
		}

	}

	public static void main(String[] args) throws IOException {
		BufferedReader in;
		File f = new File("entrada");
		if (f.exists()) {
			in = new BufferedReader(new FileReader(f));
		} else
			in = new BufferedReader(new InputStreamReader(System.in));

		int d[] = readInts(in.readLine().trim());
		w = readInts(in.readLine().trim());
		b = readInts(in.readLine().trim());
		v = new Node[w.length];

		int index = 0;
		for (int i = 0; i < b.length; i++) {
			boolean r = false;
			for (int j = 0; j < index; j++) {
				if (v[j].book == b[i]) {
					r = true;
				}
			}
			if (!r) {
				v[index] = new Node(b[i], w[b[i] - 1]);
				index++;
			}
		}

		long res = 0;
		index = 0;
		Node temp = null;

		for (int i = 0; i < b.length; i++) {

			for (int j = 0; j < v.length; j++) {
				if (v[j].book == b[i]) {
					index = j;
					temp = v[j];
					break;
				}
			}
			for (int j = index; j > 0; j--) {
				res += v[j - 1].w;
				v[j] = v[j - 1];
			}
			v[0] = temp;
		}
		System.out.println(res);

	}
}
