Php tree type instance

This article mainly introduces the php tree type, which involves the tree structure of data structures and algorithms. the instances are relatively simple and easy to understand. it has some reference value for learning data structures, for more information about php tree classes, see the example in this article. Share it with you for your reference. The specific analysis is as follows:

The principle of this instance is simple. after learning the data structure, you can see what it means. However, when using the data, the subnode id (71) appears) less than the parent node id (104 ). as a result, the part of the node is not stored in the array. the instance code is modified as follows:

The code is as follows:

<? Php
Class tree
{
Var $ data = array ();
Var $ child = array (-1 => array ());
Var $ layer = array (-1 =>-1 );
Var $ parent = array ();
Var $ num = array ();

Function setnode ($ id, $ parent, $ value, $ num = 0)
{
$ Parent = $ parent? $ Parent: 0;

$ This-> data [$ id] = $ value;
$ This-> num [$ id] = $ num;
If (! Isset ($ this-> child [$ id]) $ this-> child [$ id] = array ();
$ This-> child [$ parent] [] = $ id;
$ This-> parent [$ id] = $ parent;

If (! Isset ($ this-> layer [$ parent]) & $ parent = 0)
{
$ This-> layer [$ id] = 0;
}
Else
{
$ This-> layer [$ id] = $ this-> layer [$ parent] + 1;
}
}

Function getlist (& $ tree, $ root = 0)
{
Foreach ($ this-> child [$ root] as $ key => $ id)
{
$ Tree [] = $ id;
If ($ this-> child [$ id]) $ this-> getlist ($ tree, $ id );
}
}

Function getvalue ($ id)
{
If ($ this-> layer [$ id] = 0)
{
Return $ this-> data [$ id];
}
Else
{
Return $ leftmar. $ this-> data [$ id];
}
}

Function getnum ($ id)
{
Return $ this-> num [$ id];
}

Function getbitvalue ($ id)
{
Return $ this-> data [$ id];
}

Function getlayer ($ id, $ space = false)
{
Return $ space? Str_repeat ($ space, $ this-> layer [$ id]): $ this-> layer [$ id];
}

Function getparent ($ id)
{
Return $ this-> parent [$ id];
}

Function getparents ($ id)
{
While ($ this-> parent [$ id]! =-1)
{
$ Id = $ parent [$ this-> layer [$ id] = $ this-> parent [$ id];
}

Ksort ($ parent );
Reset ($ parent );

Return $ parent;
}

Function getchild ($ id)
{
Return $ this-> child [$ id];
}

Function getchilds ($ id = 0)
{
$ Child = array ($ id );
$ This-> getlist ($ child, $ id );

Return $ child;
}

Function printdata ()
{
Return $ this-> layer;
}
}
?>

I hope this article will help you with PHP programming.