菜单
很久没用php了，为了加深数据结构的基本知识（为考试准备），练习一下基本的算法，当然还是为了以后使用php做菜单的时候免得麻烦。
算法：数据结构中的最基本的树与二叉树的转换
大家凑合着看吧！因为只是为了熟悉一下算法，没有做具体的测试，同时对数据库的操作没有封装成类，大家如果需要可以自行修改或者和我联系！
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($j=1;$jitems["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 "
";
echo "
";
$i=$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 "
";
echo "
";
$i=$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 "
";
echo "
";
$i=$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 "
";
$i=$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 "
";
$i=$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 "
";
echo "
";
$this->items["r_node][$i]"]=-1;
}
if(($this->items["l_node][$i]"]==$current_node)) {//his parent use left point
echo "
";
echo "
";
$this->items["l_node][$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 {
$Messages=mysql_fetch_array($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");
}
}
";
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