题目描述

输入一个链表，反转链表后，输出新链表的表头。

分析

典型的面试题以及大学数据结构课程常见题，没啥好分析的了...

代码实现

递归版

function ListNode(x){    this.val = x;    this.next = null;}function ReverseList(h){    if(h === null || h.next === null)        return h;        var reversedHead = ReverseList(h.next);        h.next.next = h;    h.next = null;        return reversedHead;}

非递归版

function ListNode(x){    this.val = x;    this.next = null;}function ReverseList(h){    if(h === null || h.next === null)        return h;        var pre = null;    var cur = h;    while(cur !== null) {        var next = cur.next;        cur.next = pre;        pre = cur;        cur = next;    }        return pre;}