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Python coding interview challenges

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Re: Python coding interview challenges

#31

Post by humanrebar »

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 agree 95%. However, inevitably there will be a developer that will want to implement a trie for reasons. It's hard to be able to reason with her (or technical leadership when appealing the decision) when advocating for an off the shelf alternative if you can't explain why this isn't a brand new problem. On the flip side, one actually does need to create a new data structure on occasion, and obviously there we would want to be able to implement the common alternatives.

Anyway, it's complicated. Especially when hiring for technical leadership.

Re: Python coding interview challenges

#32

Post by stuaxo »

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…

As a fullstack developer most of these things are not needed. Having a good understanding of what is optimal is good, but you shouldn't have to be able to recite all the big O notation.

Funnily enough none of the tests I've had ever talk about relevant things like data normalisation / de-normalisation or anything that will be used in the project.

Re: Python coding interview challenges

#33

Post by throwaway2016a »

In a way I prefer this to "how many ping pong balls can fit in a school bus" that was all the rage in the 90s and early 2000s. But... man...

I have a computer science degree, I've been coding for 20 years, and I've held (and kept) a CTO role at two mid-sized startup companies. Currently I'm considering looking for a job at a larger company (where I wouldn't be CTO but I'd be hopefully paid more) and these kind of questions make me think I need to almost go back to school before I can start interviewing.

When did it get to the point where we need to read thick books on programming interviews and spend hundreds of hours on HackerRank practicing algorithms to get a job where we probably won't use any of those day-to-day?

Edit:

For fun the other day I decided to code a linked-list from scratch in C and it took me a half-hour plus... and I have known that data structure for decades. I can't imagine doing a harder problem under the pressure of being an interview.

Re: Python coding interview challenges

#34

Post by bogomipz »

nickpeterson wrote: post #4

"Before we hire you, we first need you to outwit this burmese python..."

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 mention the Hacker Rank challenge was being asked before even speaking to a human being about the job?

Re: Python coding interview challenges

#35

Post by kclay »

I recently tried for the second time to apply to some agency type place. I have 10yrs of coding, worked with big data, have done micro coding( developed protocols for vending machine transactions), done frontend and backend small and large scale.

But this place had 3 of these type of challenges that you had 1hr 30mins to complete all of them. I'm sorry, most of this stuff you will NOT find in any job unless its some specialty. For an backend/angular/react developer you will not find this at all. I feel that companies that do this are out of touch with the correct way to find candidates. But on the second hand I also see why they do this since programming has became so much popular now a days.

Re: Python coding interview challenges

#36

Post by emidln »

brianwawok wrote: post #23
riebschlager wrote: post #8

Earlier quoted context omitted.

I'd rather take my chances with a snake than trying to solve "Add two integers without using + or -".

sum([5,6]) ?

    Traceback (most recent call last):
      File "", line 1, in 
      File "", line 2, in one_true_addition_test_case
    AssertionError
The "correct" answer according to my pet parrot is (5).__add__(6). Of course, as per real-life, "correct" is usually just an aspect of if you find the interviewer's solution instead of whether your solution is actually correct. Better luck next time!

Re: Python coding interview challenges

#37

Post by tedmiston »

brianwawok wrote: post #23
riebschlager wrote: post #8

Earlier quoted context omitted.

I'd rather take my chances with a snake than trying to solve "Add two integers without using + or -".

sum([5,6]) ?

The sum built-in is still using the addition operator with syntactic sugar though (as is the other child comment). I think the intent of this question is to solve it with bitwise operators ie, [1].

[1]: http://stackoverflow.com/questions/17342042/why-this-code-fo...

Re: Python coding interview challenges

#38

Post by vonmoltke »

humanrebar wrote: post #31
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 agree 95%. However, inevitably there will be a developer that will want to implement a trie for reasons. It's hard to be able to reason with her (or technical leadership when appealing the decision) when advocating for an off the shelf alternative if you can't explain why this isn't a brand new problem. On the flip side, one actually does need to create a new data structure on occasion, and obviously there we would…

If I need to convince another developer that a particular path is well-worn and that they are drifting towards NIH syndrome I have the benefit of time to develop an argument and resources with which to do so. I do not have 45 minutes, no resources, and just a whiteboard.

To pre-counter an expected objection, if your company makes significant decisions like that in a single 45-minute (or any length, really) meeting you need to change your design process, not your hiring process.

Re: Python coding interview challenges

#39

Post by jacquesm »

bogomipz wrote: post #34
nickpeterson wrote: post #4

"Before we hire you, we first need you to outwit this burmese python..."

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…

These companies carrying water for Hacker Rank and their ilk ought to be totally ignored.

Programming is only a competition sport when it is voluntary, no need to turn access to a job into some kind of Christians versus the lions spectator sport.

If someone were to approach me with that kind of offer I think the response would not be much longer than one line (and I'd try hard to keep it polite).

Re: Python coding interview challenges

#40

Post by bogomipz »

gigatexal wrote: post #3

The advent of all of these coding challenge excercises makes not being able to do one in an interview a real show stopper. Glad there's all this material to learn from.

It's really amazing a whole industry has now sprouted up around hacking the interview process - you have interview boot camps, specific books about cracking the coding interview, mock interviews services with actual S.V engineers. As long as you have memorized how to reverse the last k elements of a doubly linked list you are probably a safe hire.
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