深度优先搜索算法（DFS,Depth First Search）的PHP实现

<?php
class Search_Method
{
//无向图的数组描述
private $dfs_save;

//全局记录数组
private $arr;

//控制分支-
private $k = 0;

public function __construct()
{
$this->dfs_save = array(
array(0,1,1,1,0,0,0,0,0),
array(1,0,0,0,1,0,0,0,0),
array(1,0,0,0,0,1,0,0,0),
array(1,0,0,0,0,0,1,0,0),
array(0,1,0,0,0,1,0,0,1),
array(0,0,1,0,1,0,0,1,0),
array(0,0,0,1,0,0,0,0,0),
array(0,0,0,0,0,1,0,0,0),
array(0,0,0,0,1,0,0,0,0),

);
$this->arr = array();
}

//深度优先搜索的递归实现方法
public function dfs($v)
{
//对顶点做一些操作
echo str_repeat("-",$this->k);
echo 'V'.($v+1).'<br>';

//记录已访问的顶点
$this->arr[]= $v;

//查找与顶点相连接的顶点，如果存在就继续深度优先搜索
for($i=0;$i<9;$i++)
{
if(!in_array($i,$this->arr)&&$this->dfs_save[$v][$i]==1)
{
$this->k++;
$this->dfs($i);
}
}
$this->k--;
return;
}
}
?>