PortalsNotYetWorking

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Portali {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String[] inpStart = br.readLine().split(" ");
        int startRow = Integer.parseInt(inpStart[0]);
        int startCol = Integer.parseInt(inpStart[1]);
        String[] inpSize = br.readLine().split(" ");
        int rows = Integer.parseInt(inpSize[0]);
        int cols = Integer.parseInt(inpSize[1]);

        int[][] matrix = new int[rows][cols];

        for (int i = 0; i < rows ; i++) {
            String[] temp = br.readLine().split(" ");
            for (int j = 0; j < cols ; j++) {
                if (temp[j].equals("#")) {
                    matrix[i][j] = -1;
                } else {
                    matrix[i][j] = Integer.parseInt(temp[j]);
                }
            }
        }
        printMatrix(matrix);

        int[] maxi = new int[1];
        boolean[][] visited = new boolean[rows][cols];
        dfs(matrix, visited, maxi, startRow, startCol, 0, 0);
        System.out.println(maxi[0]);
    }

    private static void dfs(int[][] matrix, boolean[][] visited, int[] max, int row, int col, int current, int previousValue) {

        if (row < 0 || col < 0 || row >= matrix.length || col >= matrix[0].length) {
            current -= previousValue;
            max[0] = Math.max(max[0], current);
            return;
        }
        int value = matrix[row][col];

        if (visited[row][col] || value < 0) {
            current -= previousValue;
            max[0] = Math.max(max[0], current);
            return;
        }

        current += value;
        visited[row][col] = true;

        dfs(matrix, visited, max, row + value, col, current, value);

        dfs(matrix, visited, max, row - value, col, current, value);

        dfs(matrix, visited, max, row, col + value, current, value);

        dfs(matrix, visited, max, row, col - value, current, value);

        visited[row][col] = false;

        current -= previousValue;
        max[0] = Math.max(max[0], current);

    }

    private static void printMatrix(int[][] matrix) {
        System.out.println();
        for (int i = 0; i < matrix.length; i++) {
            for (int j = 0; j < matrix[0].length; j++) {
                System.out.print(matrix[i][j] + " ");
            }
            System.out.println();
        }
    }
}