全部 ［抄题］: Reverse a singly linked list. ［思维问题］: 以为要用dummy node ［一句话思路］: 直接全部转过来就行了,用dummy node反而多余 ［输入量］:空: 正常情况:特大:特小:程序里处理到的特殊情况:异常情况(不合法不合理的输入): ［画图］: ［一刷］: return curt错了,应该是prev ［总结］: 完全转过来之后,最早的prev应该是null ［复杂度］:Time complexity: O(1) Space comple…

206. 反转链表 206. Reverse Linked List 题目描述 反转一个单链表. 每日一算法2019/5/19Day 16LeetCode206. Reverse Linked List 示例: 输入: 1->2->3->4->5->NULL 输出: 5->4->3->2->1->NULL 进阶: 你可以迭代或递归地反转链表.你能否用两种方法解决这道题? Java 实现 ListNode 类 class ListNode { in…

2018-09-11 22:58:29 一.Reverse Linked List 问题描述: 问题求解: 解法一:Iteratively,不断执行插入操作. public ListNode reverseList(ListNode head) { if (head == null) return null; ListNode dummy = new ListNode(-1); dummy.next = head; ListNode cur = head; ListNode then = nul…

[题目要求直接翻转链表,而非申请新的空间] 这道题的一个关键在于,当m=1时,需要翻转的链表段前没有其他的结点(leetcode的测试用例不含头结点),这个特例给解题带来了一点小小的困难.一个比较直观.比较方便的想法是在链表中插入一个头结点,这样处理起来方便很多.除此之外,还要注意各种循环边界条件的设置. /** * Definition for singly-linked list. * struct ListNode { * int val; * struct ListNode *next;…

Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. k is a positive integer and is less than or equal to the length of the linked list. If the number of nodes is not a multiple of k then left-out nodes in…

Reverse a singly linked list. Example: Input: 1->2->3->4->5->NULL Output: 5->4->3->2->1->NULL Follow up: A linked list can be reversed either iteratively or recursively. Could you implement both? 反转一个单链表. 示例: 输入: 1->2->…

［抄题］: 给你一个链表以及一个k,将这个链表从头指针开始每k个翻转一下.链表元素个数不是k的倍数,最后剩余的不用翻转. ［思维问题］: ［一句话思路］: // reverse head->n1->..->nk->next.. // to head->nk->..->n1->next.. // return n1 每k个转一次,再递归 ［输入量］:空: 正常情况:特大:特小:程序里处理到的特殊情况:异常情况(不合法不合理的输入): ［画图］: ［一刷］: h…

反转一个单链表. Reverse a singly linked list. 示例: 输入: 1->2->3->4->5->NULL 输出: 5->4->3->2->1->NULL 进阶: 你可以迭代或递归地反转链表.你能否用两种方法解决这道题? Follow up: A linked list can be reversed either iteratively or recursively. Could you implement both?…

/** * Definition for singly-linked list. * struct ListNode { * int val; * struct ListNode *next; * }; */ struct ListNode* reverseList(struct ListNode* head) { if(!head||!head->next) return head; struct ListNode *cur=head; struct ListNode *tail=head;…

C++解法一:迭代法,使用前驱指针pre,当前指针cur,临时后继指针nxt: /** * Definition for singly-linked list. * struct ListNode { * int val; * ListNode *next; * ListNode(int x) : val(x), next(NULL) {} * }; */ class Solution { public: ListNode* reverseList(ListNode* head) { ListN…

92. 反转链表 II 92. Reverse Linked List II 题目描述 反转从位置 m 到 n 的链表.请使用一趟扫描完成反转. 说明: 1 ≤ m ≤ n ≤ 链表长度. LeetCode92. Reverse Linked List II中等 示例: 输入: 1->2->3->4->5->NULL, m = 2, n = 4 输出: 1->4->3->2->5->NULL Java 实现 public class ListNo…

​ 请判断一个链表是否为回文链表. Given a singly linked list, determine if it is a palindrome. 示例 1: 输入: 1->2 输出: false 示例 2: 输入: 1->2->2->1 输出: true 进阶: 你能否用 O(n) 时间复杂度和 O(1) 空间复杂度解决此题? Follow up: Could you do it in O(n) time and O(1) space? 解题思路: 首先是寻找链表中间节…

Reverse a linked list from position m to n. Do it in one-pass. Note: 1 ≤ m ≤ n ≤ length of list. Example: Input: 1->2->3->4->5->NULL, m = 2, n = 4 Output: 1->4->3->2->5->NULL /** * Definition for singly-linked list. * struct…

题目 翻转链表 II 翻转链表中第m个节点到第n个节点的部分 样例 给出链表1->2->3->4->5->null, m = 2 和n = 4,返回1->4->3->2->5->null 注意 m,n满足1 ≤ m ≤ n ≤ 链表长度 挑战 在原地一次翻转完成 解题 九章中的程序 /** * Definition for ListNode * public class ListNode { * int val; * ListNode next;…

Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. If the number of nodes is not a multiple of k then left-out nodes in the end should remain as it is. You may not alter the values in the nodes, only nod…

Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. If the number of nodes is not a multiple of k then left-out nodes in the end should remain as it is. You may not alter the values in the nodes, only nod…

1. Reverse Linked List 题目链接 题目要求: Reverse a singly linked list. Hint: A linked list can be reversed either iteratively or recursively. Could you implement both? 初想用递归来实现应该会挺好的,但最终运行时间有点久,达到72ms,虽然没超时.具体程序如下: /** * Definition for singly-linked list. *…

Reverse a singly linked list. 做II之前应该先来做1的,这个倒是很简单,基本上不用考虑什么,简单的链表反转而已: /** * Definition for singly-linked list. * struct ListNode { * int val; * ListNode *next; * ListNode(int x) : val(x), next(NULL) {} * }; */ class Solution { public: ListNode* rev…

表不支持随机查找,通常是使用next指针进行操作. 206. 反转链表 /** * Definition for singly-linked list. * struct ListNode { * int val; * ListNode *next; * ListNode(int x) : val(x), next(NULL) {} * }; */ //时间:O(n) 只遍历了一遍链表 //空间:O(1) 开了三个指针的空间 class Solution { public: ListNode*…

Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. k is a positive integer and is less than or equal to the length of the linked list. If the number of nodes is not a multiple of k then left-out nodes in…

Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. k is a positive integer and is less than or equal to the length of the linked list. If the number of nodes is not a multiple of k then left-out nodes in…

Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. k is a positive integer and is less than or equal to the length of the linked list. If the number of nodes is not a multiple of k then left-out nodes in…

Reverse a singly linked list. click to show more hints. Hint: A linked list can be reversed either iteratively or recursively. Could you implement both? 之前做到Reverse Linked List II 倒置链表之二的时候我还纳闷怎么只有二没有一呢,原来真是忘了啊,现在才加上,这道题跟之前那道比起来简单不少,题目为了增加些许难度,让我们分别用…

Reverse a linked list from position m to n. Do it in-place and in one-pass. For example:Given 1->2->3->4->5->NULL, m = 2 and n = 4, return 1->4->3->2->5->NULL. Note:Given m, n satisfy the following condition:1 ≤ m ≤ n ≤ lengt…

Reverse a linked list from position m to n. Do it in one-pass. Note: 1 ≤ m ≤ n ≤ length of list. Example: Input: 1->2->3->4->5->NULL, m = 2, n = 4 Output: 1->4->3->2->5->NULL 很奇怪为何没有倒置链表之一,就来了这个倒置链表之二,不过猜也能猜得到之一就是单纯的倒置整个链表,而这…

Reverse a linked list from position m to n. Do it in-place and in one-pass. For example:Given 1->2->3->4->5->NULL, m = 2 and n = 4, return 1->4->3->2->5->NULL. Note:Given m, n satisfy the following condition:1 ≤ m ≤ n ≤ lengt…

Reverse a singly linked list. Hint: A linked list can be reversed either iteratively or recursively. Could you implement both? 反向链表,分别用递归和迭代方式实现. 递归Iteration: 新建一个node(value=任意值, next = None), 用一个变量 next 记录head.next,head.next指向新node.next,新 node.next…

Reverse Linked List 描述 反转一个单链表. 示例: 输入: 1->2->3->4->5->NULL    输出: 5->4->3->2->1->NULL 进阶: 你可以迭代或递归地反转链表.你能否用两种方法解决这道题? 解析 设置三个节点pre.cur.next (1)每次查看cur节点是否为NULL,如果是,则结束循环,获得结果 (2)如果cur节点不是为NULL,则先设置临时变量next为cur的下一个节点 (3)让cur…

Reverse a linked list. Have you met this question in a real interview? Yes Example For linked list 1->2->3, the reversed linked list is 3->2->1 Challenge Reverse it in-place and in one-pass LeetCode上的原题,请参见我之前的博客Reverse Linked List. 解法一: class…

题目来源 https://leetcode.com/problems/reverse-linked-list-ii/ Reverse a linked list from position m to n. Do it in-place and in one-pass. For example:Given 1->2->3->4->5->NULL, m = 2 and n = 4, return 1->4->3->2->5->NULL. Note:G…