php multi dementsional array hierarchy : hello everyone please i want toknow how can i get the hierarchy by the identifier.
this is an example :

    $inputArray = array(
			array(
				"text" => "Dir1",
				"parent_id" => "",
				"id" => "1",
				"filesize" => "109"
		),array(
			"text" => "dir2",
			"parent_id" => "",
			"id" => "2",
			"filesize" => "88",
			"children" => array(
					"text" => "Dir3",
					"parent_id" => "2",
					"id" => "3",
					"filesize" => "",
					"children" => array(
						"text" => "dir4",
						"parent_id" => "3",
						"id" => "4",
						"filesize" => "",
						"children" => array(
							"text" => "dir5",
							"parent_id" => "4",
							"id" => "4",
							"filesize" => ""
						)
					)
			)
		));
looking for this example : 

    dir3/dir4/dir5