11、反转链表(含源码)
题目:
反转链表
描述:
输入一个链表,反转链表后,输出链表的所有元素。
<?php
/*class ListNode{var $val;var $next = NULL;function __construct($x){$this->val = $x;}
}*/
function ReverseList($pHead)
{if($pHead == null){return null;}$pre = null;while($pHead != null){$tmp = $pHead->next;$pHead->next = $pre;$pre = $pHead;$pHead = $tmp;}return $pre;
}