Given a binary tree, return the bottom-up level order traversal of its nodes' values. (ie, from left to right, level by level from leaf to root). For example:Given binary tree [3,9,20,null,null,15,7], 3 / \ 9 20 / \ 15 7 return its bottom-up level or…
Given an n-ary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example, given a 3-ary tree: We should return its level order traversal: [ [1], [3,2,4], [5,6] ] Note: The depth of the tree is…
A + B Problem Too Time Limit: 3000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 13465 Accepted Submission(s): 10008 Problem Description This problem is also a A + B problem,but it has a little difference,…
Preface Validating data is a common task that occurs throughout all application layers, from the presentation to the persistence layer. Often the same validation logic is implemented in each layer which is time consuming and error-prone. To avoid dup…
题目 Source http://acm.hdu.edu.cn/showproblem.php?pid=4971 Description There's a company with several projects to be done. Finish a project will get you profits. However, there are some technical problems for some specific projects. To solve the proble…
