import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;


public class MatrixMaxSum {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = Integer.parseInt(scanner.nextLine());
        int[][] matrix = new int[n][];
        for (int i = 0; i < n; i++) {
            String[] numbers = scanner.nextLine().split("\\s");
            matrix[i] = new int[numbers.length];
            for (int j = 0; j < numbers.length; j++) {
                matrix[i][j] = Integer.parseInt(numbers[j]);
            }
        }

        ArrayList<Integer> allSum = new ArrayList<>();
        String[] tokens = scanner.nextLine().split("\\s+");

        for (int i = 0; i < tokens.length - 1; i += 2) {
            int col = Integer.parseInt(tokens[i]);
            int row = Integer.parseInt(tokens[i + 1]);

            int sum = 0;
            //col+
            if (col > 0) {
                col--;
                //row+
                if (row > 0) {
                    row--;
                    for (int currCol = 0; currCol <= col; currCol++) {
                        sum += matrix[currCol][row];
                    }
                }
                //row-
                else {
                    row++;
                    row *= -1;
                    for (int currCol = col; currCol < matrix.length; currCol++) {
                        sum += matrix[currCol][row];
                    }
                }
                for (int currRow = 0; currRow < row; currRow++) {
                    sum += matrix[col][currRow];
                }
            }
            //col-
            else {
                col++;
                col *= -1;
                //row+
                if (row > 0) {
                    row--;
                    for (int currCol = col; currCol >= 0; currCol--) {
                        sum += matrix[currCol][row];
                    }
                }
                //row-
                else {
                    row++;
                    row *= -1;
                    for (int currCol = col; currCol < matrix.length; currCol++) {
                        sum += matrix[currCol][row];
                    }
                }
                for (int currRow = row + 1; currRow < matrix[0].length; currRow++) {
                    sum += matrix[col][currRow];
                }
            }

            allSum.add(sum);
        }

        Collections.sort(allSum);
        System.out.println(allSum.get(allSum.size() - 1));

    }
}