找迷宫出路

<?php

function findRoad($arr){
    $position = new Position($arr);
    $road = new Road($position);
    while ($road->next() != [9,9]){
        if($road->road->isEmpty()){
            return false;
        }
    }
    printMap($road->position->map);
    return true;
}

function printMap($map){
    $str = '';
    foreach ($map as $key => $value){
        foreach ($value as $key2 => $item){
            if($key2 == 9){
                $str .= $item.PHP_EOL;
                break;
            }
            $str .= $item." ";
        }
    }
    echo $str;
}

class Position{

    public $position;

    public $map;

    public function __construct($map)
    {
        $this->map = $map;
        $this->position = [0,0];
    }

    public function isValid(){
        if ($this->map[$this->position[0]][$this->position[1]] == 0 || $this->map[$this->position[0]][$this->position[1]] == '*'){
            return false;
        }
        return true;
    }

    public function current(){
        return $this->position;
    }

    public function up(){
        if($this->position[0] == 0){
            return false;
        }
        $this->position[0] -= 1;
        if($this->isValid()){
            return true;
        }else{
            $this->position[0] += 1;
            return false;
        }
    }

    public function down(){
        if($this->position[0] == 9){
            return false;
        }
        $this->position[0] += 1;
        if($this->isValid()){
            return true;
        }else{
            $this->position[0] -= 1;
            return false;
        }
    }

    public function left(){
        if($this->position[1] == 0){
            return false;
        }
        $this->position[1] -= 1;
        if($this->isValid()){
            return true;
        }else{
            $this->position[1] += 1;
            return false;
        }
    }

    public function right(){
        if($this->position[1] == 9){
            return false;
        }
        $this->position[1] += 1;
        if($this->isValid()){
            return true;
        }else{
            $this->position[1] -= 1;
            return false;
        }
    }

    public function setZero(){
        $this->map[$this->position[0]][$this->position[1]] = 0;
    }

    public function setStar(){
        $this->map[$this->position[0]][$this->position[1]] = '*';
    }

}

class Road{

    public $road;

    public $position;

    public $direction;

    public function __construct(Position $position)
    {
        $this->road = new SplStack();
        $this->position = $position;
        $this->direction = [
            'up','down','left','right'
        ];
    }

    public function next(){
        if($this->road->isEmpty()){
            $this->road->push($this->position->position);
            $this->position->setStar();
        }
        $canNext = false;
        foreach ($this->direction as $value){
            $res = $this->position->$value();
            if($res == true){
                $canNext = true;
                $this->road->push($this->position->position);
                $this->position->setStar();
                break;
            }
        }

        if(!$canNext){
            $this->position->setStar();
            $this->back();
        }

        return $this->position->position;
    }

    public function back(){
        $this->road->pop();
        if($this->road->isEmpty()){
            $this->position->position = [0,0];
        }else{
            $this->position->position = $this->road->top();
        }
    }
}

$arr = [
    [1,0,1,1,1,0,1,1,1,0],
    [1,0,1,0,1,0,1,0,1,0],
    [1,0,1,0,1,0,1,0,1,0],
    [1,0,1,0,1,0,1,0,1,0],
    [1,0,1,0,1,0,1,0,1,0],
    [1,0,1,0,1,0,1,0,1,0],
    [1,0,1,0,1,0,1,0,1,0],
    [1,0,1,0,1,0,1,0,1,0],
    [1,0,1,0,1,0,1,0,1,0],
    [1,1,1,0,1,1,1,1,1,1],
];

findRoad($arr);