Untitled

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Scanner;
import java.util.stream.Collectors;

public class Solution {

    // Function to get maximum sum of beauties of two non-intersecting sub-grids
    public static int get_ans(int N, List<List<Integer>> A) {
        int maxSum = Integer.MIN_VALUE;

        // Transpose 2D List to 2D Array for easier manipulation
        int[][] grid = new int[N][N];
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++) {
                grid[i][j] = A.get(i).get(j);
            }
        }

        for (int size1 = 1; size1 <= N; size1++) {
            for (int r1 = 0; r1 + size1 <= N; r1++) {
                for (int c1 = 0; c1 + size1 <= N; c1++) {
                    int beauty1 = calculateBeauty(grid, r1, c1, size1);

                    for (int size2 = 1; size2 <= N; size2++) {
                        for (int r2 = 0; r2 + size2 <= N; r2++) {
                            for (int c2 = 0; c2 + size2 <= N; c2++) {
                                if (areNonIntersecting(r1, c1, size1, r2, c2, size2)) {
                                    int beauty2 = calculateBeauty(grid, r2, c2, size2);
                                    maxSum = Math.max(maxSum, beauty1 + beauty2);
                                }
                            }
                        }
                    }
                }
            }
        }

        return maxSum;
    }

    private static int calculateBeauty(int[][] grid, int r, int c, int size) {
        int maxVal = Integer.MIN_VALUE;
        int minVal = Integer.MAX_VALUE;
        for (int i = r; i < r + size; i++) {
            for (int j = c; j < c + size; j++) {
                maxVal = Math.max(maxVal, grid[i][j]);
                minVal = Math.min(minVal, grid[i][j]);
            }
        }
        return maxVal - minVal;
    }

    private static boolean areNonIntersecting(int r1, int c1, int size1, int r2, int c2, int size2) {
        // Ensure that the two sub-grids do not overlap by checking rows and columns
        return (r1 + size1 <= r2 || r2 + size2 <= r1) && (c1 + size1 <= c2 || c2 + size2 <= c1);
    }

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int N = Integer.parseInt(scan.nextLine().trim());
        List<List<Integer>> A = new ArrayList<>(N);
        
        for (int i = 0; i < N; i++) {
            A.add(Arrays.stream(scan.nextLine().trim().split(" "))
                         .map(Integer::parseInt)
                         .collect(Collectors.toList()));
        }

        int result = get_ans(N, A);
        System.out.println(result);
    }
}