Problem Reason Reference Moving ZeroesSort Colors Corner cases   Shortest Word Distance Thought: 2 ptr chasing   Merge 2 sorted ListsRemove Linked List Elem Corner cases   Power of Four Thought: fun bit ops   Pow(x, n) int overflow   Rectangle Area T…

Potential Pythonic Pitfalls Monday, 11 May 2015 Table of Contents Not Knowing the Python Version Obsessing Over One-Liners Initializing a set the Wrong Way Misunderstanding the GIL Using Old Style Classes Iterating the Wrong Way Using Mutable Default…

------------------------------------------------------------------------------------ SPA SPA(单页面应用):A single-page application (SPA) is a web application or web site that fits on a single web page with the goal of providing a user experience similar t…

好多同学跑来问,用spss的时候使用多重插补的数据集,怎么选怎么用?是不是简单的选一个做分析?今天写写这个问题. 什么时候用多重插补 首先回顾下三种缺失机制或者叫缺失类型: 上面的内容之前写过,这儿就不给大家翻译了,完全随机缺失,缺失量较小的情况下你直接扔掉或者任你怎么插补都可以,影响不大的.随机缺失可以用多重插补很好地处理:非随机缺失,任何方法都没得救的,主分析做完之后自觉做敏感性分析才是正道:这个我好像在之前的文章中给大家解释过原因. When it is plausible that da…

Given an array with n integers, you need to find if there are triplets (i, j, k) which satisfies following conditions: 0 < i, i + 1 < j, j + 1 < k < n - 1 Sum of subarrays (0, i - 1), (i + 1, j - 1), (j + 1, k - 1) and (k + 1, n - 1) should be…

An N x N board contains only 0s and 1s. In each move, you can swap any 2 rows with each other, or any 2 columns with each other. What is the minimum number of moves to transform the board into a "chessboard" - a board where no 0s and no 1s are 4…

Given a binary tree, find the length of the longest path where each node in the path has the same value. This path may or may not pass through the root. Note: The length of path between two nodes is represented by the number of edges between them. Ex…

http://jasonjl.me/blog/2015/03/30/practical-programming-practice-services/ Codewars, Leetcode, Hackerrank. Online Judges Reviews written March 30, 2015 in algorithms, programming, review Sometimes the projects you work on just aren’t stimulating enou…

1.题目 Given an unsorted array, find the maximum difference between the successive elements in its sorted form. Try to solve it in linear time/space. Return 0 if the array contains less than 2 elements. You may assume all elements in the array are non-…

These days a lot of websites allow users to upload files, but many don’t know about the unknown pitfalls of letting users (potential attackers) upload files, even valid files. What’s a valid file? Usually, a restriction would be on two parameters: Th…