SEARCH KEYWORD -- INTERVIEW QUESTION


  Select top 3 values from each group in a table with SQL

Yesterday, my friend Liu Bing asked me a question about how to select top 3 values for each person in a database table using SQL. I think this question is interesting and it deserves some thoughts. Here I record down how to solve this issue. Assume we have a table which has two columns, one column contains the names of some people and the other column contains some values related to each person. One person can have more than one value. Each value has a numeric type. The question is we want to se...

   SQL,Correlated query,top 3     2013-05-23 03:21:25

  The significance of coding competition to actual work

Some friends asked this question: In secondary schools we participate in the NOI, in university we participate in ACM/ICPC, TopCoder.What's the significance of coding competition to actual work? I participated in the NOI from 1994 to 1996, ACM/ICPC from 1999 to 2000 and TopCoder in 2002 for six months. Later I paid little attention to coding competition, so I may not understand the changes in recent years and race mode . The capabilities we can get by participating the competition can be summari...

   ACM,Programming,Facebook,TopCoder     2013-02-28 20:38:23

  JavaScript interview questions

This post will cover the JavaScript questions I have encountered and have seen during my programming career. They will mainly focus on vanilla JavaScript though there are lots of excellent frameworks out there and many people are using them in their daily work. this keyword this keyword is an very important but easy to confuse concept in JavaScript since it is always referring to the calling object of the function. 1. What will be the output of below code snippet? function User(name) { this....

   JAVASCRIPT,ALGORITHM,THIS,CLOSURE     2019-03-09 07:05:46

  Bill Gates : Ctrl+Alt+Del was a mistake

Microsoft chairman Bill Gates admitted that Ctrl+Alt+Del command was a mistake when he was in a fund raising campaign at Harvard University last week. This command was initially designed to reboot the system. David Rubenstein, the Harvard fund raising campaign chairman, asked Bill Gates : "Why when I turn on my software or computer do I need to have my three fingers to press control,alt and delete? Whose idea was that?" The answer given by Bill Gates is : "Basically because when you turn your co...

   Bill Gates,Ctrl-Alt-Del,Mistake     2013-09-26 23:28:37

  Baidu may withdraw from NASDAQ

Baidu, the search engine giant in China, may withdraw from NASDAQ some day and then get re-listed on A-shares market in China. This message is conveyed by Robin Li, CEO of Baidu, on a Wednesday(Beijing time) interview. Baidu is now investing heavily on O2O(Online to Offline) service as it is an emerging market where all Internet giants in China are diving in. In addition to its own O2O products, which include delivery service Waimai and deals site Nuomi, it has invested in a number of othe...

   NASDAQ,ROBIN LI,O2O,BAIDU     2015-09-17 04:03:55

  Convert JKS to BKS using keytool

There are lots of questions(question 1, question 2) on Stackoverflow about how to convert JKS keystore to BKS keystore(a keystore format provided by BouncyCastle) using Java keytool.  The reason why this conversion gets lots of questions is that BKS is not a keystore format supported by Java SE, it's a third party keystore format. To convert JSK to BKS, the BKS provider has to be downloaded first. And a few more options needs to be added when running the keytool command. The typical co...

   JKS,BKS,KEYTOOL,JAVA,SECURITY     2016-07-14 03:49:52

  Will nil == nil be true in GoLang

There is some interview question may ask whether nil == nil be true in GoLang. Wil it be true. false or compilation error? To know the answer, some knowledge about nil in GoLang needs to be explained first. nil definition According to Go's official documentation, the definition of nil is // nil is a predeclared identifier representing the zero value for a // pointer, channel, func, interface, map, or slice type. var nil Type // Type must be a pointer, channel, func, interface, map, or slice type...

   GOLANG,NIL,NIL EXPLANATION     2021-08-08 02:54:15

  Some thoughts about competitive programming

Many programmers may have experience in participating different kinds of coding competition while they are in college. Many of them are hired by top IT companies for their excellent performance during these kinds of coding competitions. There are some famous competitions organized by IT companies such as Google Code Jam, Facebook hackathons etc. Coding competitions are places where programmers can show their talents in programming and the skills they have. Usually programmers will solve some to...

   Coding,competition     2014-03-02 07:26:21

  Tom Uglow from Google : 5 steps to innovation

Google has been known for its innovation In Google there is a "welfare": each employee can spare 20% of his/her time to do what he/she likes to do so that any idea has a chance to be turned into reality. Perhaps this freedom makes Google capable of introducing new products and new ideas continuously. Google China held a small discussion session in its office in Tsinghua Science Park recently, Google Creative Director Tom Uglow shared some experience and cases of Google in production and innovat...

   Innovation,Technology,Google     2012-10-10 20:00:47

  Jack Ma : Where are you going during the weekends?

Jack Ma, the Chinese e-commerce giant Alibaba founder and executive chairman, was reported to show up in a night club named Dragon-i in Hong Kong on 17th August night (Beijing Time).  It became the headline in China soon after this news was reported as many people thought it was quite unusual that a successful and super rich business man like him would show up in night clubs. Jack Ma explained on his Weibo(China's Twitter) on this and he posted a question to people as well which ...

   Alibaba, Jack Ma, Night club, Bar, Hong Kong     2015-08-23 02:42:59

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