PHP单链表的基本操作

前提

对于大多数的大一，大二的童鞋们来说，可能最操蛋的就是数据结构这个课了，什么链表，堆栈，队列，图，简直噩梦！对我也是，我也是在大三后实习后发现这个真的是个硬技能，

链表的实现

数据结构第一个就是链表了，链表分为两种有直接的数组形式的顺序链，这里不讨论，什么array_push(),array_pop()，函数基本能满足日常的需求，但报告老板，我就是想装个X

上代码吧

<?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;
$arr=array('gbw','michael','php','js');//$node->getHeadCreateSLL($arr);//print_r($node->getAllElem());$node->getTailCreateSLL($arr);echo $node->getElemForPos(2);
$pos=$node->getElemPosition('gbw');echo $pos;
$node->getDeleteElem($pos);
$node->getInsertElem(1,'gbw2');
print_r($node->getAllElem());

希望对大家的php程序设计有所帮助！

作者：michaelgbw
链接：https://www.jianshu.com/p/c571d7347023