豆腐脑是咸的

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

Given a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list.For example,Given 1->2->3->3->4->4->5, return 1->2->5.Given 1->1-

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 

Sort a linked list using insertion sort.写的有点乱，有时间再写一遍Source/** * Definition for singly-linked list. * public class ListNode { * int val; * ListNode next; * ListNode(int x) { *

Given a list, rotate the list to the right by k places, where k is non-negative.For example:Given 1->2->3->4->5->NULL and k = 2,return 4->5->1->2->3->NULL.注意：这题是rotate 就像是把链表首尾相连，然后向右翻转，所以

Given a linked list, return the node where the cycle begins. If there is no cycle, return null.Follow up:Can you solve it without using extra space?先用一个指针走一步，另一个指针走两步的方法判断是否存在回路，如果存在，则将其中一个指

Sort a linked list in O(n log n) time using constant space complexity.学习了网上的帖子，用归并排序，注意空间复杂度超了，记得重做Source/** * Definition for singly-linked list. * class ListNode { * int val; * Li

Given a linked list, swap every two adjacent nodes and return its head.For example,Given 1->2->3->4, you should return the list as 2->1->4->3.Your algorithm should use only constant space. Y

Given a linked list, determine if it has a cycle in it.Follow up:Can you solve it without using extra space?设两个指针，一个走两步，一个走一步，如果有环，快的一定会和慢的汇合Source/** * Definition for singly-linked

Given a linked list and a value x, partition it such that all nodes less than x come before nodes greater than or equal to x.You should preserve the original relative order of the nodes in each of

Merge k sorted linked lists and return it as one sorted list. Analyze and describe its complexity.merge two sorted lists那道题的升级版。Source/** * Definition for singly-linked list. * public class

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.Source

Write a program to find the node at which the intersection of two singly linked lists begins.For example, the following two linked lists:A: a1 → a2 ↘

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 t

Given a linked list, remove the nth node from the end of list and return its head.For example, Given linked list: 1->2->3->4->5, and n = 2. After removing the second node from the end, the

Given a sorted linked list, delete all duplicates such that each element appear only once.For example,Given 1->1->2, return 1->2.Given 1->1->2->3->3, return 1->2->3.Source/** * Defini

You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a link

A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null.Return a deep copy of the list.这道题和clone graph那道题不同的地方在于，图可以d

Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST.和Convert Sorted Array to Binary Search Tree的区别是array可以用二分法，而list没法直接算mid。这时可用双指针，一个走快一个走慢