Sharing of basic operation examples of PHP singly linked list

<?php
 
/**
 *@author:gongbangwei(18829212319@163.com)
 *@version:1.0
 *@date:2016-05-22
 *单链表的基本操作
 *1.初始化单链表 __construct()
 *2.清空单链表 clearSLL()
 *3.返回单链表长度 getLength()
 *4.判断单链表是否为空 getIsEmpty()
 *5.头插入法建表 getHeadCreateSLL()
 *6.尾插入法建表 getTailCreateSLL()
 *7.返回第$i个元素 getElemForPos()
 *8.查找单链表中是否存在某个值的元素 getElemIsExist()
 *9.单链表的插入操作 getInsertElem()
 *10.遍历单链表中的所有元素 getAllElem()
 *11.删除单链中第$i个元素 getDeleteElem()
 *12.删除单链表所有重复的值 getElemUnique()
 **/
 header("content-type:text/html;charset=UTF-8");
 class LNode{
    public $mElem;
    public $mNext;
    public function __construct(){
        $this->mElem=null;
        $this->mNext=null;
    }
}
class SingleLinkedList{
     //头结点数据
    public $mElem;
    //下一结点指针
    public $mNext;
    //单链表长度
    public static $mLength=0;
    public function __construct(){
        $this->mElem=null;
        $this->mNext=null;
    }
    //返回单链表长度
      public static function getLength(){
          return self::$mLength;
    }
      public function getIsEmpty(){
          if(self::$mLength==0 && $this->mNext==null){
              return true;
          }
          else{
              return false;
          }
      }
      public function clearSLL(){
             if(self::$mLength>0){
                while($this->mNext!=null){
                        $q=$this->mNext->mNext;
                        $this->mNext=null;
                        unset($this->mNext);
                        $this->mNext=$q;
               }
           self::$mLength=0;
        }
    }
    public function getHeadCreateSLL($sarr){
        $this->clearSLL();
 
        if(is_array($sarr) and count($sarr)>0){
            foreach ($sarr as $key => $value) {
                $p= new LNode;
                $p->mElem=$value;
                $p->mNext=$this->mNext;
                $this->mNext=$p;
                self::$mLength++;
            }
        }
        else{
            return false;
        }
        return true;
    }
     public function getTailCreateSLL($sarr){
        $this->clearSLL();
 
        if(is_array($sarr) and count($sarr)>0){
                $q=$this;
                foreach($sarr as $value){
                        $p=new LNode;
                        $p->mElem=$value;
                        $p->mNext=$q->mNext;
                        $q->mNext=$p;
                        $q=$p;
                        self::$mLength++;
               }
        }
        else{
                return false;
        }
    }
     public function getElemForPos($i){
         if(is_numeric($i) && $i<self::$mLength && $i>0){
             $p=$this->mNext;
             for ($j=1; $j < $i ; $j++) {
                 $q=$p->mNext;
                 $p=$q;
             }
             return $p->mElem;
         }
         else{
             return null;
         }
     }
      public function getElemIsExist($value){
          if($value){
              $p=$this;
              while($p->mNext!=null and $p->mElem!=value){
                  $q=$p->mNext;
                 $p=$q;
              }
              if($p->mElem==value){
                  return true;
              }
              else{
                  return false;
              }
          }
      }
      public function getElemPosition($value){
          if($value){
              $p=$this;
              $pos=0;
              while($p->mNext!=null and $p->mElem!=$value){
                  $q=$p->mNext;
                 $p=$q;
                 $pos++;
              }
              if($p->mElem==$value){
                  return $pos;
              }
              else{
                  return -1;
              }
          }
      }
           /*单链表的插入操作
     *
     *@param int $i 插入元素的位序，即在什么位置插入新的元素,从1开始
     *@param mixed $e 插入的新的元素值
     *@return boolean 插入成功返回true，失败返回false
     */
           public function getInsertElem($i,$e){
               if($i<self::$mLength){
                   $j=1;
                   $p=$this;
               }
               else{
                   return false;
               }
               while($p->mNext!=null and $j<$i){
                   $q=$p->mNext;
                 $p=$q;
                 $j++;
               }
               $q=new LNode;
               $q->mElem=$e;
               $q->mNext=$p->mNext;
               $p->mNext=$q;
               self::$mLength++;
               return true;
           }
      /**
     *删除单链中第$i个元素
     *@param int $i 元素位序
     *@return boolean 删除成功返回true,失败返回false
     */
    public function getDeleteElem($i){
        if($i>self::$mLength || $i<1){
                return false;
            }
            else{
                $p=$this;
                $j=1;
                while($j<$i){
                    $p=$p->mNext;
                    $j++;
                }
                $q=$p->mNext;
                $p->mNext=$q->mNext;
                unset($q);
                self::$mLength--;
                return true;
            }
    }
     public function getAllElem(){
         $all=array();
         if(!$this->getIsEmpty()){
             $p=$this->mNext;
             while($p->mNext){
                 $all[]=$p->mElem;
                 $p=$p->mNext;
             }
             if($p->mElem)
                 $all[]=$p->mElem;
             return $all;
         }
     }
     public function getElemUnique(){
            if(!$this->getIsEmpty()){
                $p=$this;
                while($p->mNext!=null){
                        $q=$p->mNext;
                        $ptr=$p;
                        while($q->mNext!=null){
                                if(strcmp($p->mElem,$q->mElem)===0){
                                    $ptr->mNext=$q->mNext;
                                    $q->mNext=null;
                                    unset($q->mNext);
                                    $q=$ptr->mNext;
                                    self::$mLength--;
                                }
                                else{
                                    $ptr=$q;
                                    $q=$q->mNext;
                                }
                      }
                      //处理最后一个元素
                   if(strcmp($p->mElem,$q->mElem)===0){
                                $ptr->mNext=null;
                                self::$mLength--;
                        }
                        $p=$p->mNext;
                }//end of while
            }   
    }
}
 
///////////////test//////////
$node=new SingleLinkedList;
$arr=array(&#39;gbw&#39;,&#39;michael&#39;,&#39;php&#39;,&#39;js&#39;);
//$node->getHeadCreateSLL($arr);
//print_r($node->getAllElem());
$node->getTailCreateSLL($arr);
echo $node->getElemForPos(2);
$pos=$node->getElemPosition(&#39;gbw&#39;);
echo $pos;
$node->getDeleteElem($pos);
$node->getInsertElem(1,&#39;gbw2&#39;);
print_r($node->getAllElem());