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Python coding interview challenges

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Re: Python coding interview challenges

#71

Post by septimus111 »

jacquesm wrote: post #56
septimus111 wrote: post #44

Earlier quoted context omitted.

I agree that these interviews are often just an annoying rite of passage, and they exclude many very talented programmers, but dismissing companies that use them as 'incompetent' seems like a stretch to me. Learning basic data structures & algorithms is an immensely useful thing for a programmer, and completely essential in many cases. The best of these puzzles are based on problems which people have had to solve in…

It's just laziness incarnate. This pushes all the investment of the first phase of interviewing someone onto an automated process and denies the candidate the opportunity to vet the company which is just as important as the reverse. Well, actually they do allow the candidate to vet the company: the message they send is we don't care about you at all until you do a bunch of busywork and if you're very lucky we might a…

How are companies supposed to evaluate candidates without giving them some form of busywork? The best way I can think of is to pay them to complete a project but that's not possible when you are interviewing loads of candidates.

Re: Python coding interview challenges

#73

Post by sidlls »

numbsafari wrote: post #43
sparkling wrote: post #17

Semi off-topic, but i am curious. How much of CS fundamentals do you expect a backend (or fullstack) developer to recite in an job interview? I did all CS theory stuff many years ago at university, but i could not pass a interview test full with these CS basics. Isn't it far more important to know how to design a modern, maintainable, scalable web application? Know how an when to cache stuff. How to design a API. How…

> Isn't it far more important to know how to design a modern, maintainable, scalable web application? Know how an when to cache stuff. How to design a API. How do you do that without some basic understanding of computer science-y stuff? How do you define "scalable", how do you measure it? How can you have some intuition about a design before we spend 3 months and many sprints building it first? How do I know when to…

> How do you do that without some basic understanding of computer science-y stuff?

What do you mean by "understand"? In some ways your question is like asking an engineer how he can choose a particular bolt for use in, say, an elevator, without understanding the basics of how the failure characteristics of the bolt are known. There's some relationship there, but is it really an important one? Sometimes it may be. Other times (most times?) probably not.

> How do you define "scalable", how do you measure it? How can you have some intuition about a design before we spend 3 months and many sprints building it first?

"Scalable" is entirely dependent on the business' needs and plans, and measuring it certainly doesn't require any formal understanding of computer science. This is fairly basic arithmetic. As for the design intuition: computer science-y things are only so useful as far as that goes. Their real utility is in optimization, not designing ahead of time.

> I can't see myself hiring a computer programmer who is offended by being expected to have a casual acquaintance with computer science.

Well, as you yourself noted, questions of this sort aren't for "casual acquaintance" levels of knowledge. These kinds of exercises are basically things an undergrad (or, in some cases, graduate) student thinks are important because they're all he knows.

Incidentally, the fact that interviews focus so much on these kinds of "CS fundamentals" is one reason I chuckle whenever somebody tries to describe these companies' activities as "engineering." Any engineering that goes on in places that put much weight to these kinds of questions, and which isn't interviewing candidates specifically to engage in academic, or close-to-research CS, day-to-day, is usually by accident.

Re: Python coding interview challenges

#74

Post by duiker101 »

swalsh wrote: post #68
cauterized wrote: post #27

I see these challenges as a great way for excellent experienced developers to weed out incompetent companies. I'm a kick-ass get-things-done full-stack web engineer. I've never had to deal with one of these sorts of problems in my day to day work; and if I did, I'd just find an existing, tested, stable library that already handled them. A company that needs someone to solve these sorts of problems doesn't want me on…

I was going to agree with you, 98% of my career has been "google for a library, then use or tweak". It's RARE we ever actually do anything "new". However there ARE companies that do, and every once in a while YOU may have to do something new. In those cases it's good to make sure you have a foundation to build on. I have 4 books in the "The art of computer programming" series on my desk. They've been more or less dec…

In that 2% of the cases where you have to come up with something new, I don't really think that knowing pretty much any of this would help. You are storing a lot of information that will probably never be used. On the other hand, knowing how to come up with the solution. Knowing where to ask, what books to read or what people to ask, seems like a more important skill.

Re: Python coding interview challenges

#75

Post by bogomipz »

user5994461 wrote: post #70
bogomipz wrote: post #34

Earlier quoted context omitted.

Indeed. A couple of weeks ago I had a recruiter from Atlassian send me an email saying they were interested an could I complete these 6 problems on Hacker Rank and each challenge has a time limit. Its not enough to outwit a Burmese Python but you need to do it while a clock is ticking. We all know the best performance and indicator of skill always comes from coding with an egg timer or stop watch. Oh and did I mentio…

> Oh and did I mention the Hacker Rank challenge was being asked before even speaking to a human being about the job? I prefer that a lot more than scheduling a 1 hour phone interview during my workday, to do the same stupid questions over the phone, with someone who can describe neither the job nor the company.

Sure, that scenario is equally broken and happened to me with a big S.V company recently. If the company can't even schedule an interview with someone on the actual team then I'm probably not interested in the company and can and have cut the phone interview short upon learning that.

Re: Python coding interview challenges

#76

Post by quantumhobbit »

gpderetta wrote: post #64
cauterized wrote: post #27

I see these challenges as a great way for excellent experienced developers to weed out incompetent companies. I'm a kick-ass get-things-done full-stack web engineer. I've never had to deal with one of these sorts of problems in my day to day work; and if I did, I'd just find an existing, tested, stable library that already handled them. A company that needs someone to solve these sorts of problems doesn't want me on…

I'm a lowly c++ software engineer. You might not have to deal with that stuff, but for me it was Tuesday. Kidding aside, someone has to build those tested, stable libraries that handle those problem (or even untested bleeding-edge if you are breaking new ground).

Where does one get a job writing actual algorithms and data structures? I actually enjoy that and am pretty good at it. I'm sick of jobs that are nothing but glueing together poorly documented and tested libraries.

Re: Python coding interview challenges

#77

Post by bigtimeidiot »

hashkb wrote: post #61
cauterized wrote: post #27

I see these challenges as a great way for excellent experienced developers to weed out incompetent companies. I'm a kick-ass get-things-done full-stack web engineer. I've never had to deal with one of these sorts of problems in my day to day work; and if I did, I'd just find an existing, tested, stable library that already handled them. A company that needs someone to solve these sorts of problems doesn't want me on…

> I'm a kick-ass get-things-done full-stack web engineer. And modest, too. If an engineer gave me your answer ("I never learned the principle because I never had to") I would know they aren't a fit for my team.

>If an engineer gave me your answer ("I never learned the principle because I never had to") I would know they aren't a fit for my team

So we should learn all the things, ahead of time, just in case we get an interview question at some point in life?

Re: Python coding interview challenges

#78

Post by duiker101 »

gpderetta wrote: post #64
cauterized wrote: post #27

I see these challenges as a great way for excellent experienced developers to weed out incompetent companies. I'm a kick-ass get-things-done full-stack web engineer. I've never had to deal with one of these sorts of problems in my day to day work; and if I did, I'd just find an existing, tested, stable library that already handled them. A company that needs someone to solve these sorts of problems doesn't want me on…

I'm a lowly c++ software engineer. You might not have to deal with that stuff, but for me it was Tuesday. Kidding aside, someone has to build those tested, stable libraries that handle those problem (or even untested bleeding-edge if you are breaking new ground).

This is very true, but I don't think that anyone interviewing for a position like yours will reference to this list of things to test their candidates.

Re: Python coding interview challenges

#79

Post by jacquesm »

septimus111 wrote: post #71
jacquesm wrote: post #56

Earlier quoted context omitted.

It's just laziness incarnate. This pushes all the investment of the first phase of interviewing someone onto an automated process and denies the candidate the opportunity to vet the company which is just as important as the reverse. Well, actually they do allow the candidate to vet the company: the message they send is we don't care about you at all until you do a bunch of busywork and if you're very lucky we might a…

How are companies supposed to evaluate candidates without giving them some form of busywork? The best way I can think of is to pay them to complete a project but that's not possible when you are interviewing loads of candidates.

Introduce them to the team they will be working with, have them do a code review or take a ticket and find their way through docs and discuss a potential solution.

In general teams are a much better judge of talent and ability than recruiters or your typical interviewer, especially in a normal work setting.

Re: Python coding interview challenges

#80

Post by sidlls »

cauterized wrote: post #27

I see these challenges as a great way for excellent experienced developers to weed out incompetent companies. I'm a kick-ass get-things-done full-stack web engineer. I've never had to deal with one of these sorts of problems in my day to day work; and if I did, I'd just find an existing, tested, stable library that already handled them. A company that needs someone to solve these sorts of problems doesn't want me on…

> I see these challenges as a great way for excellent experienced developers to weed out incompetent companies.

This is far too broad. There are plenty of jobs in certain companies where a good understanding of the theory and practice encapsulated by these challenges is the bare-minimum requirement for doing well. Companies that leverage coding challenges like these for these positions aren't incompetent (at least, not for that reason). Just because your work doesn't require this depth of understanding of CS doesn't mean there is no such work.

I'm skeptical, however, that the number of such jobs is very large, even in the "usual suspects" companies (Google, Amazon, etc.). Most jobs, even in these places, one can get by with the most rudimentary ability to understand what 'greater than' and 'lesser than' means and a chart describing time/space complexities of various structures and algorithms in a library.

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