Programmers: Your favorite interview questions

[FightAndLive]

I haven't seen one these posts yet on this forum(if there is forgive me : )), but I figured to help out more people looking for programming work I would start a post for employers who are looking to hire new programmers what kind of questions you guys ask. I'm the technical director at a small game studio in LA, and were expanding so I also looking to see what everyone does so I can adjust accordingly.

Some of the basic questions I ask are:

What is global scope/local scope.

What is a template class

What is inheritance/polymorphism/etc.

Than some really basic logic stuff like whats a recursive function, etc etc.

Than I begin to ask a couple questions that are kind of off the wall because one thing I noticed is College graduates from big schools such as UCLA 9/10 can't figure stuff for themselves. Students are so used to stuff getting spoon fed to them, some of which is just nasty. One thing that really irritated me at one of the studios I worked at previously a couple of there senior programmers came to me and said "I don't know how to do xyz, can you help?" This normally is a pretty common thing, except when xyz happens over and over again and its something that easily be found by doing a quick google search.

I ask the interviewee if they can do something that 99% of the programmers out there can't do. They would obviously say I don't know, I would then ask them than to look it up for me on google and write out basic steps on how to get it done. Lets say I ask them how to register a custom Debug Engine in Visual Studio, first google search for "visual studio custom debug engine" which turns up http://msdn.microsof...4(v=vs.80).aspx , with a link to http://msdn.microsof...(v=vs.110).aspx. Even though the information on the latter article is actually wrong if they copied that I would be so happy. I've had guys sit there for 10 minutes struggling, and I feel that's kind of ridiculous. Every programmer in world should know how to use google :/.

Than depending on the level of the job, I would go into some more nitpicker things say in Unreal, Unity, D3D, whatever and if someone didn't know the answer I would ask them to google it and give me an explanation. I had actually had one guy who didn't graduate from a college, straight out of high school and he didn't know something I asked him, and than he immediately asked if he could go on google and look it up. I actually hired him on the spot and he ones of the best programmers I've ever had.

Anyway what kind of stuff do you guys ask?

[Praetor]

Well, there is our main difference: Im not passionate about code, I just want to write code to get me paid :)

 

as a sysadmin that takes care of hundreds of servers, that attitude bothers me; i've seen software made by top companies in my country so badly done and inefficient that hurts the clients (wallets), like requiring 16GB of RAM in a server just for an app, as an example i've recently found, not even mentioning the amount of RAM for SQL, etc.

 

funny thing is: when i questioned one of the project managers of one of those companies about the lack of optimization and high resources, the amount of crap that came out of his mouth showed what that they care is the paycheck, not the costumers (short signed because now they are gonna lose this same client).

[snaphat (Myles Landwehr) Member]

For weighing a recursive implementation versus iterative, there are several factors to consider. But in the end, if it's a perf critical path, the real answer is "measure, measure, measure."

The point in the explicit stack + iteration case I gave though is that it is just a recursive solution expressed explicitly. You are just reimplementing the call stack by hand and that's basically always going to be slower in practice than letting the memory be handled by the call stack. There are numerous reasons why, such as, algorithmic choices for the manual stack implementation, sanity checking when pushing/popping, introducing additional subroutine calls; or to say it another way: you increase the operation count & moved from direct stack allocation (via the call stack) to using heap allocation (via the explicit stack).

 

Going back to what I was originally saying, in terms of it taking more time to write efficient code versus not: all you are really doing in these types of cases is spending a lot of time trying to optimize out recursion for not because in the end you just end up re-implementing a recursive solution that looks iterative. And what's more is that it is less efficient in practice but doesn't look like it is to many people outside of compilers so the "efficient" implementation ends up staying in the code base  ;)

[riahc3]

as a sysadmin that takes care of hundreds of servers, that attitude bothers me; i've seen software made by top companies in my country so badly done and inefficient that hurts the clients (wallets), like requiring 16GB of RAM in a server just for an app, as an example i've recently found, not even mentioning the amount of RAM for SQL, etc.

 

funny thing is: when i questioned one of the project managers of one of those companies about the lack of optimization and high resources, the amount of crap that came out of his mouth showed what that they care is the paycheck, not the costumers (short signed because now they are gonna lose this same client).

At the end of the day the most important thing is the paycheck. Well actually making sure that your customers keep buying your product which gives you a paycheck.

Note the words: I said "making sure your customers keeping buying your product". I never said anything about "making sure your customers are happy". Big difference.

But at the end of the day, I guess people that like to program dont worry about the paycheck too much and do want to make their customers happy.

[Andre S. Veteran]

We don't look for programmers, we look for solution providers, individuals that are passionate about the code they write, the way they work with other developers as well as our end users. They are valued contributors to the success of the company, not just a room full of 'coders'. Do I care if they can split a TIF image and do page manipulation in an interview. Nope... even though that might be their first problem. I care about how they think about problems and how they go about learning the things they don't know.

And that's the kind of attitude from a company that I look for in an interview. The interview process tells me a lot about the type of people that work there, and I want to work with, as you say, passionate solution providers, not "coders". I find the very idea that my job is to "produce code" abhorrent. I usually first try to solve problems by deleting code, actually, i.e. "do we really need to do this? is this code still relevant? can this be done more simply?" Code is technical debt, the less the better.

[+John Teacake MVC]

10 uses for a kettle...Seriously. 

[williamholdin]

More Interview Question and Answers...

 

http://net-informations.com/faq/default.htm

 

William

 

[Osiris]

 

I'll be honest, guys like you stand out like a sore thumb in interviews. Maybe not where you are located, but certainly in my shop. There is difference between telling someone what you think they want to hear and having a thoughtful discussion about writing code and solving problems. We don't look for programmers, we look for solution providers, individuals that are passionate about the code they write, the way they work with other developers as well as our end users. They are valued contributors to the success of the company, not just a room full of 'coders'. Do I care if they can split a TIF image and do page manipulation in an interview. Nope... even though that might be their first problem. I care about how they think about problems and how they go about learning the things they don't know.

 

That was good to read and im glad there are still companies and people out there who get this.  You need people who can just get in and code but innovation and building the sort of culture that fosters creativity, cultivates new developments and just the capacity to think outside the box to deliver client solutions, those aren't the qualities you find by asking a lot of the questions in this thread.

[wrack]

If I was then I would give them a Fizz Buzz Test + Write Simple Function to print Manager - Employee Hierarchy with Reporting Level (hint : Recursive). I have seem 99% applicants failing that.

 

I'm not an interviewer, but if I was I think I would always start with the Fizz Buzz Test. Filtering out 99.5% of incompetents with such a simple question is appealing

[Dick Montage]

FizzBuzz is BS. Everyone knows it. It's a stock question.

My current go to question is to write (language agnostic) the logic for expressing a given monetary value using the least notes and coins possible.

It's ridiculously easy but it let's you see how they work, the way they optimise code.

[+Fahim S. MVC]

FizzBuzz is BS. Everyone knows it. It's a stock question.

My current go to question is to write (language agnostic) the logic for expressing a given monetary value using the least notes and coins possible.

It's ridiculously easy but it let's you see how they work, the way they optimise code.

 

You'd be surprised how many get FizzBuzz wrong 

Your monetary value question, is that not a just a division and modulus question (not really thought about, but it can't be more complicated than that can it?)

[Dick Montage]

Your monetary value question, is that not a just a division and modulus question (not really thought about, but it can't be more complicated than that can it?)

 

It CAN be.  But it's how they do it.

 

I've had people loop with a while statement to see if the outstanding > 0, or I've had people loop through an array of denominations, heck I've had one person write way too many if statements.

 

My personal favourite (when I was solving it) was to define a class of denomination that has a rendered value and an actual value, a type of coin or note, etc.  Create an array of denominations representing the locale's currency.  Sort the array (highest to lowest) using a function to sort by the denominations actual value.  Then for each denomination, divide the outstanding balance by said value, floor it, subtract that amount.  Move to next.

[+Raphaël G. MVC]

It CAN be.  But it's how they do it.

 

I've had people loop with a while statement to see if the outstanding > 0, or I've had people loop through an array of denominations, heck I've had one person write way too many if statements.

 

My personal favourite (when I was solving it) was to define a class of denomination that has a rendered value and an actual value, a type of coin or note, etc.  Create an array of denominations representing the locale's currency.  Sort the array (highest to lowest) using a function to sort by the denominations actual value.  Then for each denomination, divide the outstanding balance by said value, floor it, subtract that amount.  Move to next.

 

I hate these tests and I would probably fail most of them. However I love coding, it's a passion. And I love to learn. My opinion: a lot of companies are just missing out on pretty damn good and passionate developers. I've seen my share of code monkeys, non-user centric and lazy developers who do pass these tests. To me, they don't prove much.

 

And to answer the original question "Programmers: Your favorite interview questions": none! Just let me write useful code dammit!

[Dick Montage]

I hate these tests and I would probably fail most of them. However I love coding, it's a passion. And I love to learn. My opinion: a lot of companies are just missing out on pretty damn good and passionate developers. I've seen my share of code monkeys, non-user centric and lazy developers who do pass these tests. To me, they don't prove much.

 

This isn't about code, it's proven itself to be about how well developers understand what is being asked.  Seriously, I have had some abhorrent interviewees recently!