摘要：
Given a binary tree, find its maximum depth.The maximum depth is the number of nodes along the longest path from the root node down to the farthest le... 阅读全文
摘要：
买一个大房子，在海边，一个二层小复式楼，爸妈都住在一起，一家人永远永远在一起~ 阅读全文
摘要：
Given an array of integers, find if the array contains any duplicates. Your function should return true if any value appears at least twice in the arr... 阅读全文