摘要： Given a linked list, return the node where the cycle begins. If there is no cycle, return null. To represent a cycle in the given linked list, we use 阅读全文

摘要： Given a non-empty string s and a dictionary wordDict containing a list of non-empty words, determine if s can be segmented into a space-separated sequ 阅读全文

摘要： There are N children standing in a line. Each child is assigned a rating value. You are giving candies to these children subjected to the following re 阅读全文

摘要： Given a non-empty array of integers, every element appears three times except for one, which appears exactly once. Find that single one. Note: Your al 阅读全文

摘要： There are N gas stations along a circular route, where the amount of gas at station i is gas[i].You have a car with an unlimited gas tank and it costs 阅读全文

摘要： Given a non-empty array of integers, every element appears twice except for one. Find that single one. Note: Your algorithm should have a linear runti 阅读全文

摘要： Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number. An example is the root-to-leaf path1->2->3 which 阅读全文

摘要： Given an unsorted array of integers, find the length of the longest consecutive elements sequence. Your algorithm should run in O(n) complexity. Examp 阅读全文

摘要： Given two words (beginWord and endWord), and a dictionary's word list, find the length of shortest transformation sequence from beginWord to endWord, 阅读全文

摘要： Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. Note: For the purpose of this problem, w 阅读全文