PHP implements reverse order of linked list

不言
Release: 2023-03-24 12:32:02
Original
1538 people have browsed it

The content of this article is about the implementation of linked list reverse order in PHP, which has certain reference value. Now I share it with everyone. Friends in need can refer to it

<?php
    class Node {
        public $str;        public $next;        function __construct ($str) {
            $this->str = $str;
        }
    }    //创建链表头
    function createList () {
        $head = new Node(null);        return $head;
    }    //向链表$head中插入节点并赋值
    function insertNode ($str, &$head) {
        $node = new Node($str);        $node->next = &$head->next;        $head->next = &$node;
    }    //取出链表的第一个节点,相当于出队
    function outQueue (&$head) {
        $tmp = $head->next;        $head->next = $head->next->next;        $tmp->next = null;        return $tmp;
    }    //将链表$head进行逆序
    function reverse (&$head) {
        $reversed = createList(null);        while (null != $head->next) {
            insertNode(outQueue($head), $reversed);
        }        return $reversed;
    }    $head = createList();
    insertNode(&#39;hello&#39;, $head);
    insertNode(&#39;world&#39;, $head);
    insertNode(&#39;99999999999999&#39;, $head);
    insertNode(&#39;888888888888888&#39;, $head);
    insertNode(&#39;7777777777777&#39;, $head);
    insertNode(&#39;66666666666666&#39;, $head);
    insertNode(&#39;55555555555&#39;, $head);
    insertNode(&#39;444444444444&#39;, $head);
    insertNode(&#39;333333333333&#39;, $head);
    insertNode(&#39;222222222222222&#39;, $head);
    insertNode(&#39;111111111111&#39;, $head);
    insertNode(&#39;000000000000000&#39;, $head);
    print_r($head);    $reversed = reverse($head);    echo "<hr />";
    print_r($reversed);    //上面的方法没有在原链表上操作,不过他创建了一个新链表,
    //虽然逻辑实现显得简单,但是太不专业
    //下面贴出更加专业的逆序代码
    function reverse2 (&$head) {
    $q = $head->next->next;    $head->next->next = null;    while (null != $q) {        $p = $q;        $q = $p->next;        $p->next = $head->next;        $head->next = $p;
    }
    reverse2($head);    echo "<hr />";
    print_r($head);
} ?>
Copy after login


Output result:
Linked list before reverse order:
Node Object ( [str] => [next] => Node Object ( [str] => 000000000000000 [next] => Node Object ( [str] ] => 111111111111 [next] => Node Object ( [str] => 222222222222222 [next] => Node Object ( [str] => 333333333333 [next] => > 444444444444 [next] => Node Object ( [str] => 55555555555 [next] => Node Object ( [str] => 66666666666666 [next] => Node Object ( [str] => 7777777777777 [next] => Node Object ( [str] => 888888888888888 [next] => Node Object ( [str] => 99999999999999 [next] => next] => Node Object ( [str] => hello [next] => ) ) ) ) ) ) ) ) ) ) ) ) ) )

The linked list after reverse order:
Node Object ( [str] => [next] => Node Object ( [str] => Node Object ( [str] => hello [next] => ) [next] => Node Object ( [str ] => Node Object ( [str] => world [next] => ) [next] => Node Object ( [str] => Node Object ( [str] => 99999999999999 [next] = > ) [next] => Node Object ( [str] => Node Object ( [str] => 888888888888888 [next] => ) [next] => Node Object ( [str] => Node Object ( [str] => 7777777777777 [next] => ) [next] => Node Object ( [str] => Node Object ( [str] => 66666666666666 [next] => ) [ next] => Node Object ( [str] => Node Object ( [str] => 55555555555 [next] => ) [next] => Node Object ( [str] => Node Object ( [ str] => 444444444444 [next] => ) [next] => Node Object ( [str] => Node Object ( [str] => 3333333333333 [next] => ) [next] => ; Node Object ( [str] => Node Object ( [str] => 222222222222222 [next] => ) [next] => Node Object ( [str] => Node Object ( [str] => ; 111111111111 [next] => ) [next] => Node Object ( [str] => Node Object ( [str] => 000000000000000 [next] => ) [next] => ) ) ) ) ) ) ) ) ) ) ) ) )

Related recommendations:

Use PHP to implement a singly linked list

How to implement a doubly linked list in PHP And sort


The above is the detailed content of PHP implements reverse order of linked list. For more information, please follow other related articles on the PHP Chinese website!

Related labels:
source:php.cn
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Popular Tutorials
More>
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template