新的开始

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 linked list, determine if it has a cycle in it.Follow up:Can you solve it without using extra space?判断一个连表是否有环，而且不使用额外空间=。=用一快一慢两个指针！class Solution {public: bool hasCycle(Lis

题目链接在此Given a singly linked list, determine if it is a palindrome.Follow up:Could you do it in O(n) time and O(1) space?要求用O(N)的时间和O(1)的空间，判断单链表是否为回文串。可以用一快一慢两个链表，溜一遍，寻找到链表的中

题目链接在此Reverse a singly linked list.反转一个单链表。别小看这道题啊，我TX面试上来就问这道题。当时我觉得用两个指针就够了——显然天真了，得用三个指针。这是一个循环的算法：struct ListNode { int val; ListNode *next; ListNode(int x) : val(x), next(NULL)

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 ↘

这是两道题。24. Swap Nodes in Pairs ： 把链表两两相邻的结点互换值。25. Reverse Nodes in k-Group ： 把链表中每k个结点组成的子链表翻转。其实24就是25在k=2时候的情况。就只讲25吧。Given a linked list, reverse the nodes of a linked list k at