t112633

import java.util.*;

public class t112633 {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        int[][] matrix = new int[n][n];

        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                matrix[i][j] = in.nextInt();
            }
        }
        in.nextLine();

        String[] a = in.nextLine().split(" ");
        int s = 0;
        for (int i = 1; i < a.length; i++) {
            int from = Integer.parseInt(a[i - 1]) - 1;
            int to = Integer.parseInt(a[i]) - 1;
            if (matrix[from][to] != 0)
                s += matrix[from][to];
            else {
                System.out.println(0);
                return;
            }
        }
        System.out.println(s);
    }
}