Ask HN: How to not fail on coding interview questions? • Hacker News Board

Re: Ask HN: How to not fail on coding interview questions?

#121

Post by daly » Tue, Jun 19, 2018, 7:38 AM UTC

borplk wrote: post #90

daly wrote: post #76

BALL-PITS and CLOWN NOSES I worked with a guy, Bob, in our college computer room. Bob had returned to get his BS after many years in industry. He had great stories. He also had great advice. He taught me that you can learn a lot about how a company will treat their employees by paying attention to the way they treat you during the interview. He suggested several sign that indicated it was best to just "walk away". If…

I agree with pretty much everything you say but the reality for the majority of people is they can't afford to "just walk away" when those things are so widespread. It was in another recent thread someone was insisting you should "just walk away" if the company doesn't have private offices. It's not practical for most people.

I agree. I'm just passing on some general life advice for interviews I got from Bob. If you're in a position to look around for other opportunities (as "the best and brightest" often are), it helps to see through the market hype. If you're actually in need of the job, do what they ask. I've been in both situations.

IBM often had "hiring freezes", nobody could hire anyone... well, except that I still did some interviews at IBM Research. There were people we would hire under any circumstance. In fact, one of the people I interviewed during a hiring freeze was offered a job and a whole new lab. She really was one of "the best and brightest". (She actually did walk away and went elsewhere.)

Do you really think that Geoff Hinton, Andrew Ng, and Yann LeCun got whiteboarded?

Re: Ask HN: How to not fail on coding interview questions?

#122

Post by ahoka » Tue, Jun 19, 2018, 11:12 AM UTC

dabockster wrote: post #68

neverminder wrote: post #33

Apply to companies that don't do whiteboarding/phoneboarding. I don't know, maybe this is a US thing, or the Big Four thing, but down here in London I am yet to encounter a company that does whiteboarding. https://github.com/poteto/hiring-without-whiteboards

If you live near enough to a tech hub, you have to assume you're going to be code screened and whiteboarded. Companies around here (Seattle) use it as a cost cutting measure so they don't have to spend time and money manually interviewing every single candidate. It's significantly cheaper to enforce a competition-style coding challenge and pick off the top 5-10% performers (example figure) of the challenge for the ac…

London is a "tech hub".

Re: Ask HN: How to not fail on coding interview questions?

#123

Post by samueldavid » Tue, Jun 19, 2018, 1:28 PM UTC

crististm wrote: post #88

samueldavid wrote: post #79

Earlier quoted context omitted.

he is just hurting himself by trying so hard on a already broken system, encouraging him to keep going at it like most of the user on this thread( Keep drilling! keep drilling!) will just make him more sad and doubt even more of his own skills which are already proven on his company to be good enough, if anything people should encourage him to try places that don't use such broken methods and go for companies that re…

Apparently you place no value in an evaluation done within a broken process - and rightfully so. I have to ask: how do you tell a good process from a bad one?

(personal opinion), but to me a process that encourages these kind of drills is pretty broken, these drills are ( most of the time) not related to the real world problems the company faces on a day to day basis, imo, a better process ( but not perfect) would be to test candidates on problems related to the ones you face at the company combined with cultural fit / pair programming sessions, even tho not perfect it can attract more candidates that are more fitting to the company and the team.

this doesn't mean the tests and problems need to be easy or an easy pass, they can be just as hard or even harder to solve, depending on the problems you guys face, i often hear people defending the drills because "people just want a for loop problem and fizzbuzz and easy pass", which is not the case for many seniors engineers that would like a decent challenge related to what the company works on.

Re: Ask HN: How to not fail on coding interview questions?

#124

Post by crististm » Tue, Jun 19, 2018, 2:34 PM UTC

samueldavid wrote: post #123

crististm wrote: post #88

Earlier quoted context omitted.

Apparently you place no value in an evaluation done within a broken process - and rightfully so. I have to ask: how do you tell a good process from a bad one?

(personal opinion), but to me a process that encourages these kind of drills is pretty broken, these drills are ( most of the time) not related to the real world problems the company faces on a day to day basis, imo, a better process ( but not perfect) would be to test candidates on problems related to the ones you face at the company combined with cultural fit / pair programming sessions, even tho not perfect it can…

If I understand you correctly, the bad issue is tests by drilling for drilling sake. I agree with you but follow me on this:

Am I wrong to say that he as one person is in no position to change the process?

What I mean is that his choices are either to just go through the hoops and reject to the drills because they are not representative for his ability, or accept this testing but not stamp negative results on his quality as a person or developer.

In the end he is not defending the process too strongly; is seems to me that he simply wants a formula to navigate it.

Re: Ask HN: How to not fail on coding interview questions?

#125

Post by drstewart » Wed, Jun 20, 2018, 2:29 AM UTC

daly wrote: post #119

monksy wrote: post #105

Earlier quoted context omitted.

I used to say this about the whiteboards. Then came the take home tests.

Send your architect home to build a rocking chair over his weekend. See if he calls you back on Monday. A take home test is a very clear statement by management that your time is less important than their process. As a professional, you only have your time and skill as your saleable assets. You have the choice of giving them away for free. You could, of course, take the test and then present them a bill for your serv…

You keep comparing developers to architects, doctors, accountants, and lawyers without realizing there's a huge difference between the latter and the former: licensing. That makes all the difference, my friend.

Re: Ask HN: How to not fail on coding interview questions?

#126

Post by JoachimSchipper » Wed, Jun 20, 2018, 5:18 AM UTC

tzs wrote: post #109

JoachimSchipper wrote: post #96

Earlier quoted context omitted.

> Can you still solve it in O(N) time and O(1) space if when your code returns the answer the input must be unchanged? I don't think that is possible in general. In some cases, such as your "small integers only" case, the program can get extra working memory by essentially compressing the input, doing some work in the freed-up memory, and uncompressing; but if the input memory is already used optimally, there should…

(Note: this comment contains spoilers for the original problem and for my proposed variation) (Note: I'm going to use Python3-based pseudo code, except I'm going to assume 1-based array numbers, so the input is in a[1], a[2], a[3], ..., a[N].) Suppose the input input list has N integers. Then the smallest positive integer not in the list must be one of 1, 2, 3, ..., N+1. (Prove by noting that all positive integers le…

I was indeed thinking of (1), albeit just using radix sort - your permutation trick is nicer.

But (2) doesn't work in general, because information theory may not allow storing more information in the input array than is already there; I'm convinced myself, but I haven't come up with a better argument than "obvious" in the time I had available. ;-)

Re: Ask HN: How to not fail on coding interview questions?

#127

Post by eivarv » Wed, Jun 20, 2018, 11:54 AM UTC

drstewart wrote: post #125

daly wrote: post #119

Earlier quoted context omitted.

Send your architect home to build a rocking chair over his weekend. See if he calls you back on Monday. A take home test is a very clear statement by management that your time is less important than their process. As a professional, you only have your time and skill as your saleable assets. You have the choice of giving them away for free. You could, of course, take the test and then present them a bill for your serv…

You keep comparing developers to architects, doctors, accountants, and lawyers without realizing there's a huge difference between the latter and the former: licensing. That makes all the difference, my friend.

Honest question: what does licensing solve/prove that transcripts and/or certifications don't?

Re: Ask HN: How to not fail on coding interview questions?

#128

Post by daly » Wed, Jun 20, 2018, 9:00 PM UTC

drstewart wrote: post #125

daly wrote: post #119

Earlier quoted context omitted.

Send your architect home to build a rocking chair over his weekend. See if he calls you back on Monday. A take home test is a very clear statement by management that your time is less important than their process. As a professional, you only have your time and skill as your saleable assets. You have the choice of giving them away for free. You could, of course, take the test and then present them a bill for your serv…

You keep comparing developers to architects, doctors, accountants, and lawyers without realizing there's a huge difference between the latter and the former: licensing. That makes all the difference, my friend.

Good point. Technically, according to your metric, programmers are not "Professionals", licensed to practice their art.

On the other hand, if you have a degree and years of experience, would a license matter? I wouldn't object to licensing for programmers. At least there would be common standards, not random whiteboarding.

Of course, you realize that licensing has a dangerous downside. If you're a licensed programmer and your company get hacked because of your bug, you would be liable. If your code fails to detect a pedestrian or fails to brake, you're liable for murder. If the Ariane rocket is destroyed and a multi-million dollar satellite is destroyed, you're now deeply in debt. If your Therac 25 software makes a mistake, again... murder. So be careful what you wish for.

At a robot company I worked for we agonized over this. Could a robot, driven by our software, accidently kill someone? To get around this we put up hardware safeguards; chain link fences with kill switches on gates, pressure pads with kill switches on floors, and any other hardware we could invent. In theory, we programmers were not liable, but if we were licensed we probably would have been.

So, yeah, license programmers. Require a degree. Require certification. Require certification in the language you use and yearly refresher courses. Require proof-carrying code. Require financial bonds to cover losses caused by your code. Require insurance to cover losses covered by your code.

That's probably a good solution to the whiteboarding issue.

Re: Ask HN: How to not fail on coding interview questions?

#129

Post by fitpolar » Wed, Jun 20, 2018, 9:20 PM UTC

daly wrote: post #76

BALL-PITS and CLOWN NOSES I worked with a guy, Bob, in our college computer room. Bob had returned to get his BS after many years in industry. He had great stories. He also had great advice. He taught me that you can learn a lot about how a company will treat their employees by paying attention to the way they treat you during the interview. He suggested several sign that indicated it was best to just "walk away". If…

I'd like to share a more balanced approach (sure, give me heat for fence sitting), and while I agree with the above, there's a time to walk away, and there's a time to suck it up.

I would strongly to suggest finding interviews at some stage of our lives with the pure intent to walk away from. If you feel strongly about the process, it's one thing to grumble, but this is the only way change will happen.

If you're desperate for a another job however, and are really feeling like you need to be in a new place within 6 months, then go through a phase of sucking it up, finding a daily challenge on hackerrank, and seeing if "you've still got it" with these silly problems that we all know are exclusive to undergrad studies and nowhere else.

Great analogy with the ball pit and clown nose btw, I'm going to use that.