看了版主的无限分类，分成树形结构后，怎么还原

父子无限分类

原始数组

/*
获取无线分类，对无线分类进行节点路径排列
*/
$a=array (
 0 =>
 array (
 'id' => '134',
 'fid' => '0',
 'name' => 't',
 ),
 1 =>
 array (
 'id' => '133',
 'fid' => '0',
 'name' => 'k',
 ),
 2 =>
 array (
 'id' => '132',
 'fid' => '0',
 'name' => 'j',
 ),
 3 =>
 array (
 'id' => '137',
 'fid' => '133',
 'name' => '我是k的分类1',
 ),
 4 =>
 array (
 'id' => '136',
 'fid' => '134',
 'name' => '我是t的分类t2',
 ),
 5 =>
 array (
 'id' => '135',
 'fid' => '134',
 'name' => '我是t的分类t1',
 ),
 6 =>
 array (
 'id' => '138',
 'fid' => '137',
 'name' => '我是k的分类1-1',
 ),
 7 =>
 array (
 'id' => '139',
 'fid' => '138',
 'name' => '我是k的分类1-1-1',
 ),
 8 =>
 array (
 'id' => '140',
 'fid' => '139',
 'name' => '我是k的分类1-1-1-1',
 ),
)
?>

开始形成树，并且增加路径，树形数组为$trees
Array
(
 [0] => Array
 (
 [id] => 134
 [fid] => 0
 [name] => t
 [path] => 134
 [_sub] => Array
 (
 [0] => Array
 (
 [id] => 136
 [fid] => 134
 [name] => 我是t的分类t2
 [path] => 134,136
 )

 [1] => Array
 (
 [id] => 135
 [fid] => 134
 [name] => 我是t的分类t1
 [path] => 134,135
 )

 )

 )

 [1] => Array
 (