很久沒用php了，為了加深數(shù)據(jù)結(jié)構(gòu)的基本知識（為考試準備），練習一下基本的算法，當然還是為了以后使用php做菜單的時候免得麻煩。
算法：數(shù)據(jù)結(jié)構(gòu)中的最基本的樹與二叉樹的轉(zhuǎn)換
大家湊合著看吧！因為只是為了熟悉一下算法，沒有做具體的測試，同時對數(shù)據(jù)庫的操作沒有封裝成類，大家如果需要可以自行修改或者和我聯(lián)系！


Your data must save like this:
id,topic,child_l,parent,child_r,content

file name:
show.inc.php
codes:
==================================================
<?

class shows{
var $items;
var $the_stack;
var $count=0;


function find($l_value) {
for($j=1;$j<=$this->items["info_all"];$j++) {
if($l_value==$this->items["d_id][$j]"])
{ return($j);exit; }

}

}


function m_l_r_list($i) {

if(($this->items["f_node][$i]"]==0)&&($this->items["r_node][$i]"]==0)&&($this->items["l_node][$i]"]!=-1))
{//if it is root node!!!
echo "<table><tr><td>";
echo "<img id=image".$i." src=http://cfan.net.cn/"c.gif\" onclick=outliner() style=\"cursor:hand\" child=\"".$i."ALL\" NAME=\"NAME_".$i."ALL\">";
echo "<a href=\"".$this->pages_0($this->items["d_id][$i]"])."?d_id=".$this->items["d_id][$i]"]."\" target=\"rightFrame\">".$this->items["node_value][$i]"]."</a>";
echo " <a href=addnode.php?id=".$this->items["d_id][$i]"]." target=\"rightFrame\"><font size=2 color=red>Add</font></a>";
echo "</td></tr>";
echo "<div class=collapsed id=".$i."ALL>";
$i=$this->find($this->items["l_node][$i]"]);
$this->count=$this->count+2;
$this->m_l_r_list($i);
exit;
}
if(($this->items["f_node][$i]"]==0)&&($this->items["r_node][$i]"]==0)&&($this->items["l_node][$i]"]==-1))
{
exit;
}
 if(($this->items["f_node][$i]"]!=0)&&($this->items["r_node][$i]"]!=0)&&($this->items["l_node][$i]"]!=0))
 {//if node have left and right child
 $current_node=$this->items["d_id][$i]"];
 
 if(($this->items["l_node][$i]"]==-1)&&($this->items["r_node][$i]"]==-1)) {
$i=$this->find($this->items["f_node][$i]"]);
if(($this->items["r_node][$i]"]==$current_node)) {//his parent use right point
$this->items["r_node][$i]"]=-1;
}
if(($this->items["l_node][$i]"]==$current_node)) {//his parent use left point
$this->items["l_node][$i]"]=-1;
}
$this->count=$this->count-2;
$this->m_l_r_list($i);
}//if left child and right child have been visited up to his parent node

 if(($this->items["l_node][$i]"]!=-1)&&($this->items["r_node][$i]"]!=-1)) {
echo "<table><tr><td>";
for ($k=0;$k<$this->count;$k++) { echo " ";}
echo "<img id=image".$i." src=http://cfan.net.cn/"c.gif\" onclick=outliner() style=\"cursor:hand\" child=\"".$i."ALL\" NAME=\"NAME_".$i."ALL\">";
echo "<a href=\"main.php?d_id=".$this->items["d_id][$i]"]."\" target=\"rightFrame\">".$this->items["node_value][$i]"]."</a>";
//echo $this->items["node_value][$i]"];
echo " <a href=addnode.php?id=".$this->items["d_id][$i]"]." target=\"rightFrame\"><font size=2 color=red>Add</font></a>";
echo " <a href=delnode.php?id=".$this->items["d_id][$i]"]."><font size=2 color=red>Del</font></a>";
echo "</td></tr>";
echo "<div class=collapsed id=".$i."ALL>";
$i=$this->find($this->items["l_node][$i]"]);//visite left child node
 $this->count=$this->count+2;
 $this->m_l_r_list($i);
}//if left child node and right child node have not been visited
 
 if(($this->items["l_node][$i]"]==-1)&&($this->items["r_node][$i]"]!=-1)) {
 $i=$this->find($this->items["r_node][$i]"]);//visite right child node
 $this->m_l_r_list($i);
}//if left child node have been visited and right child node have not been visited 
 
 }
 
if(($this->items["f_node][$i]"]!=0)&&($this->items["r_node][$i]"]==0)&&($this->items["l_node][$i]"]!=0))
{//if node only have left child
$current_node=$this->items["d_id][$i]"];
if($this->items["l_node][$i]"]!=-1) {
echo "<table><tr><td>";
for ($k=0;$k<$this->count;$k++) { echo " ";}
echo "<img id=image".$i." src=http://cfan.net.cn/"c.gif\" onclick=outliner() style=\"cursor:hand\" child=\"".$i."ALL\" NAME=\"NAME_".$i."ALL\">";
echo "<a href=\"main.php?d_id=".$this->items["d_id][$i]"]."\" target=\"rightFrame\">".$this->items["node_value][$i]"]."</a>";
//echo $this->items["node_value][$i]"];
echo " <a href=addnode.php?id=".$this->items["d_id][$i]"]." target=\"rightFrame\"><font size=2 color=red>Add</font></a>";
echo " <a href=delnode.php?id=".$this->items["d_id][$i]"]."><font size=2 color=red>Del</font></a>";
echo "</td></tr>";
echo "<div class=collapsed id=".$i."ALL>";
$i=$this->find($this->items["l_node][$i]"]);//visite left child node
$this->count=$this->count+2;
$this->m_l_r_list($i);
exit;
}//if his left child node have not been visited

if($this->items["l_node][$i]"]==-1) {
echo "</div>";
$i=$this->find($this->items["f_node][$i]"]);
if(($this->items["r_node][$i]"]==$current_node)) {//his parent use right point
$this->items["r_node][$i]"]=-1;
}
if(($this->items["l_node][$i]"]==$current_node)) {//his parent use left point
$this->items["l_node][$i]"]=-1;
$this->count=$this->count-2;
}
$this->m_l_r_list($i);
exit;
}//if his left child node have been visite,up to his parent node


}
if(($this->items["f_node][$i]"]!=0)&&($this->items["r_node][$i]"]!=0)&&($this->items["l_node][$i]"]==0))
{//if node only have right child
$current_node=$this->items["d_id][$i]"];
$j=$this->find($this->items["f_node][$i]"]);
if($this->items["r_node][$i]"]!=-1) {
echo "<table><tr><td>";
for ($k=0;$k<$this->count;$k++) { echo " ";}
echo "<a href=\"main.php?d_id=".$this->items["d_id][$i]"]."\" target=\"rightFrame\">".$this->items["node_value][$i]"]."</a>";
//echo $this->items["node_value][$i]"];
echo " <a href=addnode.php?id=".$this->items["d_id][$i]"]." target=\"rightFrame\"><font size=2 color=red>Add</font></a>";
echo " <a href=delnode.php?id=".$this->items["d_id][$i]"]."><font size=2 color=red>Del</font></a>";
echo "</td></tr>";
$i=$this->find($this->items["r_node][$i]"]);//visite right child node
$this->m_l_r_list($i);
exit;
}//if his right child node have not been visited

if($this->items["r_node][$i]"]==-1) {
$i=$this->find($this->items["f_node][$i]"]);
if(($this->items["r_node][$i]"]==$current_node)) {//his parent use right point
$this->items["r_node][$i]"]=-1;
}
if(($this->items["l_node][$i]"]==$current_node)) {//his parent use left point
$this->items["l_node][$i]"]=-1;
$this->count=$this->count-2;
}
$this->m_l_r_list($i);
exit;
}//if his right child node have been visite,up to his parent node


}
if(($this->items["f_node][$i]"]!=0)&&($this->items["l_node][$i]"]==0)&&($this->items["r_node][$i]"]==0))
{//if this node haven't child node,print it and up to his parent
 //node his parent left or right child have been visited
$current_node=$this->items["d_id][$i]"];
$j=$i;
$i=$this->find($this->items["f_node][$i]"]);//up to parent
//echo $this->items["l_node][$i]"];
if(($this->items["r_node][$i]"]==$current_node)) {//his parent use right point
echo "<table><tr><td>";
for ($k=0;$k<$this->count;$k++) { echo " ";}
echo "<a href=\"main.php?d_id=".$this->items["d_id][$j]"]."\" target=\"rightFrame\">".$this->items["node_value][$j]"]."</a>";
//echo $this->items["node_value][$j]"];
echo " <a href=addnode.php?id=".$this->items["d_id][$j]"]." target=\"rightFrame\"><font size=2 color=red>Add</font></a>";
echo " <a href=delnode.php?id=".$this->items["d_id][$j]"]."><font size=2 color=red>Del</font></a>";
echo "</td></tr>";
echo "</div>";
$this->items["r_node][$i]"]=-1;

}
if(($this->items["l_node][$i]"]==$current_node)) {//his parent use left point

echo "<table><tr><td>";
for ($k=0;$k<$this->count;$k++) { echo " ";}
echo "<a href=\"main.php?d_id=".$this->items["d_id][$j]"]."\" target=\"rightFrame\">".$this->items["node_value][$j]"]."</a>";
//echo $this->items["node_value][$j]"];
echo " <a href=addnode.php?id=".$this->items["d_id][$j]"]." target=\"rightFrame\"><font size=2 color=red>Add</font></a>";
echo " <a href=delnode.php?id=".$this->items["d_id][$j]"]."><font size=2 color=red>Del</font></a>";
echo "</td></tr>";
echo "</div>";
$this->items["l_node][$i]"]=-1;
$this->count=$this->count-2;

}
$this->m_l_r_list($i);
exit;
}

}

function pages_0($d_id){//
include("conn_db.php");
$Sql_Query="select * from node_page where d_id=$d_id";
$Query_Db=mysql_query($Sql_Query,$Connect);
$MyPage=mysql_fetch_array($Query_Db);
include("conn_close.php");
if($MyPage["d_page"]!='')
{
return $MyPage["d_page"];
}
else return "init.php";
}
function pages($d_id){//
include("conn_db.php");
$Sql_Query="select * from node_page where d_id=$d_id";
$Query_Db=mysql_query($Sql_Query,$Connect);
$MyPage=mysql_fetch_array($Query_Db);
include("conn_close.php");
return $MyPage["d_page"];
}

function showinfo_0($status){//
include("conn_db.php");
$Sql_Query="select * from department order by d_id";
$Query_Db=mysql_query($Sql_Query,$Connect);
$info_all=mysql_num_rows($Query_Db);
$this->items["info_all"]=$info_all;
if($status==1) {//when status=1 show all data gets from database
$MNums=$info_all;
}
if($status==0) {//when status=0 show 6 messages gets from database
$MNums=6;
}
for($i=1;$i<=$MNums;$i++)
{
$Messages=mysql_fetch_array($Query_Db);
$this->items["d_id][$i]"]=$Messages["d_id"];
$this->items["f_node][$i]"]=$Messages["f_node"];
$this->items["node_value][$i]"]=$Messages["node_value"];
$this->items["l_node][$i]"]=$Messages["l_node"];
$this->items["r_node][$i]"]=$Messages["r_node"];
}
include("conn_close.php");
}
}