剑指offer：反转链表

最新推荐文章于 2025-08-15 16:44:13 发布

转载最新推荐文章于 2025-08-15 16:44:13 发布 · 55 阅读

0 ·

CC 4.0 BY-SA版权

原文链接：http://www.cnblogs.com/zyb993963526/p/10481454.html

文章标签：

#数据结构与算法 #c/c++ #python

问题描述

输入一个链表，反转链表后，输出新链表的表头。

c++代码

 1 /*
 2 struct ListNode {
 3     int val;
 4     struct ListNode *next;
 5     ListNode(int x) :
 6             val(x), next(NULL) {
 7     }
 8 };*/
 9 class Solution {
10 public:
11     ListNode* ReverseList(ListNode* pHead) {
12         if(pHead == NULL)  return pHead;
13         ListNode *cur = pHead, *nxt, *pre = NULL;
14         while(cur != NULL){
15             nxt = cur->next;
16             cur->next = pre;
17             pre = cur;
18             cur = nxt;
19         }
20         return pre;
21     }
22 };

python代码

 1 # -*- coding:utf-8 -*-
 2 # class ListNode:
 3 #     def __init__(self, x):
 4 #         self.val = x
 5 #         self.next = None
 6 class Solution:
 7     # 返回ListNode
 8     def ReverseList(self, pHead):
 9         # write code here
10         if not pHead:
11             return pHead
12         cur, pre = pHead, None
13         while cur:
14             nxt = cur.next
15             cur.next = pre
16             pre = cur
17             cur = nxt
18         return pre