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Do we really need to interview about data structure and algorithms traditionally?

diaakhateeb profile image Diaa Elkhateeb ・2 min read

As long as you grow up in your career, you move on top of the level that you asked to implement common data structures such as linked list, stack and queue. I have graduated in 2001 where the most common libraries were C++ STL and VC++ MFC. Lots of time I have been interviewed and asked to design and implement queue, stack and list containers.

In 2002, I started to use .NET framework version 1.0 where such data structures were part of the class libraries.

Now after 15 years, I still find people ask the same questions of implementing data structures while the type of development inside the company does not require this. I prefer to ask questions that appropriate to the nature of work. I take another approach when I interview candidate. I ask him about utilizing the built-in containers such as List, Queue and HashTable. For example, I give him the below code:

    var hashTble = new HashTable();
    var diction = new Dictionary<int, string>();

Both are data containers. My questions to the candidate would be:

1- The main difference in terms of internal implementation.
2- The best scenario for each one.
3- Performance in terms of time and space.
4- If I would like to override each one Add method, what I need to do (code).
5- Iterations over each one elements.

In my opinion, through this way I can figure out If the candidate understands such fundamentals very well or not. I always believe that we have to consider the work requirements when we perform interviews. I met lots of interviewers ask complicated questions only to make shows while questions are not related to work nature at all.


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jfrankcarr profile image
Frank Carr

While I generally agree with this concept, I think it's easy to stray into turning an interview into a language trivia quiz. The .NET Framework is vast and it's relatively easy to find an area where a candidate might not have an immediate answer.

For example, I don't think I've ever used HashTable in an application. While I've heard of it, I couldn't answer specifics about it without looking it up. Since I've been working mostly in MVC and Web API the past few years, I probably wouldn't remember all of the details of WebForms and WCF stuff.