摘要：
Given a sorted array nums, remove the duplicates in-place such that each element appear only once and return the new length. Do not allocate extra spa 阅读全文
摘要：
Given an array nums and a value val, remove all instances of that value in-place and return the new length. Do not allocate extra space for another ar 阅读全文
摘要：
Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. An input string is valid if: No 阅读全文
摘要：
Given an array nums of n integers, are there elements a, b, c in nums such that a + b + c = 0? Find all unique triplets in the array which gives the s 阅读全文
摘要：
Given a binary tree Populate each next pointer to point to its next right node. If there is no next right node, the next pointer should be set to NULL 阅读全文