maze - study code written in Java

maze_studyCode.java

import java.util.*;
public class Solution {
    static final int[][] dir = {{1, 0}, {-1, 0}, {0, 1}, {0, -1}};
    public static int checkMaze(int[][] maze)
    {
        if(maze == null || maze.length == 0 || maze[0][0] == 0) return 0;
        if(maze[0][0] == 9) return 1;
        int m = maze.length, n = maze[0].length;
        Queue<int[]> queue = new LinkedList<>();
        queue.offer(new int[]{0, 0});
        maze[0][0] = 0;
        while(!queue.isEmpty())
        {
            int[] p = queue.poll();
            for(int k = 0; k < 4; k++)
            {
                int x = p[0] + dir[k][0];
                int y = p[1] + dir[k][1];
                if(x >=0 && x < m && y >= 0&& y < n)
                {
                    if(maze[x][y] == 9) return 1;
                    else if(maze[x][y] == 1)
                    {
                        queue.offer(new int[]{x, y});
                        maze[x][y] = 0;
                    }
                }
            }
        }
        return 0;
    }
    public static void printMatrix(int[][] matrix)
    {
        int m = matrix.length, n = matrix[0].length;
        for(int i = 0; i < m; i++)
        {
            for(int j = 0; j < n; j++) System.out.print(matrix[i][j] + " ");
            System.out.println("");
        }
    }
    public static void main(String[] args)
    {
        int[][] maze = {{1, 0, 0, 1}, {1, 1, 1, 1}, {1, 0, 0, 9}};
        printMatrix(maze);
        System.out.println(checkMaze(maze));
    }
}