摘要： Given a linked list, return the node where the cycle begins. If there is no cycle, return null. Note: Do not modify the linked list. Follow up:Can you 阅读全文

摘要： Given a linked list, determine if it has a cycle in it. Follow up:Can you solve it without using extra space? 判断是否成环 1、利用set，很简单，但是题目中说不要用额外的空间。 2、设置两 阅读全文

摘要： Given a string s and a dictionary of words dict, add spaces in s to construct a sentence where each word is a valid dictionary word. Return all such p 阅读全文

摘要： Given a string s and a dictionary of words dict, determine if s can be segmented into a space-separated sequence of one or more dictionary words. For 阅读全文

摘要： 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 阅读全文

摘要： Given an array of integers, every element appears three times except for one. Find that single one. Note:Your algorithm should have a linear runtime c 阅读全文