Given a singly linked list L: L0→L1→-→Ln-1→Ln,reorder it to: L0→Ln→L1→Ln-1→L2→Ln-2→- You must do this in-place without altering the nodes' values. For example,Given {1,2,3,4}, reorder it to {1,4,2,3}. 按照题意改变链表结构. 1.使用list记录链表. /** * Definition for si…

143. Reorder List https://www.cnblogs.com/grandyang/p/4254860.html 先将list的前半段和后半段分开,然后后半段进行逆序,然后再连接 class Solution { public: void reorderList(ListNode* head) { if(head == NULL) return; ListNode* p1 = head; ListNode* p2 = head; while(p2->next != NULL…

Given a singly linked list L: L0→L1→…→Ln-1→Ln, reorder it to: L0→Ln→L1→Ln-1→L2→Ln-2→… You must do this in-place without altering the nodes' values. For example, Given {1,2,3,4}, reorder it to {1,4,2,3}. 解题思路一: 每次将Ln换到前面,得到L0→Ln→L1→L2→L3→,然后对L1使用相同操作,…

一.题目描述 Given a singly linked list L: L0→L1→…→Ln-1→Ln,reorder it to: L0→Ln→L1→Ln-1→L2→Ln-2→… You must do this in-place without altering the nodes' values. For example,Given {1,2,3,4}, reorder it to {1,4,2,3}. 二.分析 1.暴力解法 这种解法所需的时间的时间复杂度比较高,为O(n2) 代码如下…

Given a singly linked list L: L0→L1→…→Ln-1→Ln,reorder it to: L0→Ln→L1→Ln-1→L2→Ln-2→… You must do this in-place without altering the nodes' values. For example,Given {1,2,3,4}, reorder it to {1,4,2,3}. 搞了一天多,纠结到一个while 写成了if........... 思路很清晰,  找出链表的中点…

Given a singly linked list L: L0→L1→…→Ln-1→Ln,reorder it to: L0→Ln→L1→Ln-1→L2→Ln-2→… You may not modify the values in the list's nodes, only nodes itself may be changed. 思路: 1.  find mid 2.  cut list 3.  reverse slow part 4.  merge two parts 代码: clas…

原题地址 先把链表分割成前后两半,然后交叉融合 实践证明,凡是链表相关的题目,都应该当成工程类题目做,局部变量.功能函数什么的随便整,代码长了没关系,关键是清楚,不容易出错. 代码: ListNode *reverseList(ListNode *head) { if (!head) return head; ListNode *prev = head; head = head->next; prev->next = NULL; while (head) { ListNode *next =…

[LeetCode]143. Reorder List 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.me/ 题目地址:https://leetcode.com/problems/reorder-list/description/ 题目描述: Given a singly linked list L: L0→L1→-→Ln-1→Ln, reorder it to: L0→Ln…

Question 143. Reorder List Solution 题目大意:给一个链表,将这个列表分成前后两部分,后半部分反转,再将这两分链表的节点交替连接成一个新的链表 思路 :先将链表分成前后两部分,将后部分链表反转,再将两部分链表连接成一个新链表 链表取中间节点思路:龟兔赛跑,每秒钟乌龟跑1步,兔子跑2步,当兔子跑完全程时乌龟正好跑完一半 链表反转实现思路 : Java实现: /** * Definition for singly-linked list. * public clas…

题目难度:Medium 题目: Given an array S of n integers, are there elements a, b, c, and d in S such that a + b + c + d = target? Find all unique quadruplets in the array which gives the sum of target. Note: The solution set must not contain duplicate quadrup…