7 ms·

Hacking the coding interview

78 points by wpnx 13y ago

AznHisoka 13y ago
"So you're interviewing at Google and lunch time comes around. Food is free so you eat way too much, especially carbs. Your post-lunch interview is a disaster since you have trouble focusing due to lethargy. True story." Ha... I might have chosen the wrong cafeteria, but to me the food was a disappointment during my Google interview. The veggies were way too hard, I didn't like tacos, some of the meat looked indecipherable, and I was fumbling as I wondered whether there was a line, or whether I was looking stupid. I kinda wished there was NO free lunch.
- wpnx 13y ago
  I think "free food" and "all you can eat" has the effect of making many people completely unreasonable in their eating habits. The cafeteria near the gift shop wasn't too bad. I appreciated the hospitality :)
- aegiso 13y ago
  I honestly can't tell whether the last sentence was intended to be a punchline or not. But if so, good job!
justinsteele 13y ago
The idea of using "B-list" companies makes me a bit disgusted honestly. Have we put ourselves on such pedestals that we use other people's valuable time as unknowing practice runs? I would never interview somewhere I was not interested in working.
- wpnx 13y ago
  I think disgusting is a bit strong of a term. The same logic can be used when applying to college (a very similar process). You apply to a bunch of schools, some of which you don't want to go to. If you have your heart set on Stanford and you don't get in, you still need to go to college somewhere. I guess the advantage of interviewing at companies that at first glance you wouldn't want to work at, means that sometimes you get convinced by talking to the great people there. I've joined at least one company that wasn't initially my first choice for this exact reason.
  - yardie 13y ago
    Maybe it's different elsewhere but every college I applied to I wanted to go to. Between the essays, interviews, application fees, and entry requirements I wouldn't waste my time applying to a place I didn't want to get in to. I've also cut an interview short once I realized it was a waste of time (H1b formality). If I'm not being taken seriously I won't take them seriously and I certainly won't waste my energy on fizzbuzz questions.
- siegecraft 13y ago
  Why not? Companies certainly have no problem interviewing B-list candidates.
  - cbr 13y ago
    Companies do not, just for practice, interview people they have no intention of hiring.
    - vonmoltke 13y ago
      Not for practice, but companies do interview people they have no intention of hiring in order to fulfil internal policies or improve diversity metrics.
      - jjoonathan 13y ago
        Don't forget H-1Bs!
    - johnnymonster 13y ago
      yea your just flat wrong.
    - ajuc 13y ago
      Why no salary range on job offers then?
- jjoonathan 13y ago
  I can think of three reasons for interviewing at a "B-list" company that have nothing to do with putting oneself on a pedestal. 1) You might actually like the work/environment/personal growth opportunities/company health at the "B-list" company once you see it in person. Admit it: your initial classification involved a healthy amount of guesswork and is probably not fantastically accurate. 2) A stupid mistake in your A-list interview hurts both you and the A-list company, potentially dramatically so. You help both them and yourself by practicing. 3) Your increased bargaining power decreases the chance the A-list company lowballs your salary, shooting both you and themselves in the foot (hiring your replacement is expensive, lost productivity due to dissatisfaction is expensive, envy-poisoned work relationships are expensive).
  - RougeFemme 13y ago
    I understand how a mistake in an A-list interview hurts you, but how does it hurt the A-list company?
    - johnnymonster 13y ago
      Because coming into an interview with your A-list unprepared is a waste of their time.
    - jjoonathan 13y ago
      Because it artificially reduces the talent pool they're drawing from. They might wind up hiring someone less competent who was better at signalling or making concessions to someone who wasn't as far ahead of the pack as they thought based on interview performance. Time and opportunity cost also factor in, of course.
- ritchiea 13y ago
  I don't think it's disgusting at all, I've known many people (not just developers) who do "trial" interviews before they apply to their A-list companies. Interviewing is a skill and if you don't practice it you won't be at your best when it's most important to you. That said, I recommend keeping your ears open and earnestly assessing whether the company may be a good fit even if it's on your "B-list".
- ajuc 13y ago
  If a company doesn't specify salary range in a job offer it's asking for trial runs to be honest. And most don't.
mountaineer 13y ago
There are some good tips and links here, but I don't understand the "hacking" metaphor. There are no big secrets. It all comes down to the "always be coding" idea that was presented a few months ago [1]. It just takes discipline and time-management. Succeed at that and many offers will come your way. [1] https://medium.com/tech-talk/d5f8051afce2 https://medium.com/tech-talk/d5f8051afce2
- wpnx 13y ago
  Great article :) Maybe not secrets, but lessons learned from the current state of the industry. Each one of the points I make is either from a mistake made in an interview I've personally given or received.
- suyash 13y ago
  Exactly, the article offers no new insights and the title is mis-represented. It has just listed what we assume we need to do in order to practice for the technical interview. Nice refresher though and I like that every thing is listed out for you.
- rtfeldman 13y ago
  The article's thesis is basically the exact opposite of this. It states in no uncertain terms that "always be coding" is wrong. That you should instead spend your time practicing techniques you never use when creating actual software, and that you should also maximize your interview count for salary leverage. "A lot of what I'm suggesting to do is pretty extreme. A lot of the skills here are not something you learn by doing a standard software engineering job (or get coming out of college). It's especially hard for more senior engineers to do technical interviews since most have limited time due to familial obligations and haven't taken CS 101 for quite some time."
DigitalSea 13y ago
I am completely against written tests or questions that ask abstract questions and ask you to write algorithms. Unless you're going for a position that requires a PhD in computer science and your job will be writing algorithms and solving overly complex problems, the pen and whiteboard approach just doesn't work in 2013. Hiring a developer shouldn't be as complicated as some companies make it out to be. Maybe for the likes of Google it has to be a lot more complex than others because they have an image and large workforce that depends on people being excellent self-managers and workers that require minimal management. For smaller companies you are wasting your time and my time asking me questions that test my ability to remember things more-so than they do to search and find answers. Lets face it, most developers these days are hackers. I've never met a developer who knows the answer to everything, I've seen the best of the best using Stackoverflow to find an answer to their question. The difference between a good developer and a great developer is knowing a little and for the stuff you don't know, knowing exactly what to Google when you encounter a problem you can't solve off of the top of your head. As Albert Einstein famously said, "Never Memorize What You Can Look Up in a Book" — that doesn't mean don't learn anything, but get the basics down and eventually you'll know what to Google when you don't know something. The real test of any developer is if they're a good fit for your team, have good work ethic and can get the job done. You can find the smartest developer in the world but they might not be a good fit for your team. Culture matters as does a good work environment with compatible people. The best way to test a developer anywhere in the world is to give them access to a computer, an IDE and their environment of choice. Then ask them to build you something. Don't ask them to write binary search code if they're being interviewed for a front-end position, ask them to build something. Welcome to your interview; build us a blog, build us a todo app, write a simple Wordpress plugin, write a jQuery plugin or what my current employer did: they brought me in for a trial for a couple of days (paid) and asked me to get my hands dirty on a real project they were currently working on. Just threw me in the deep end and after two days they had a good idea how I worked and if I was a fit.
- wpnx 13y ago
  > Don't ask them to write binary search code if they're being interviewed for a front-end position, ask them to build something. +1! Thanks for the thoughtful response; I really love the way you worded this. I agree with what you're saying; the best, most fun, challenging and fair interviews I've had have been at small companies coding side by side with somone. I wonder if it's possible to scale the "build-it" interview up to a google sized org. Another idea I've been mulling around is hiring people for an N month contract position where you get to work with them. If at the end, both parties agree its a good fit, then proceed. I can see a lot of pit falls to this approach, but it might work really well for people with strong referrals.
yanilkr 13y ago
The talk about tech interviews reminds me of this clip. http://www.youtube.com/watch?v=OXRi28W-ENY http://www.youtube.com/watch?v=OXRi28W-ENY
- WalterGR 13y ago
  The above link is to the first minute and a half of the interview sequence in the original Men in Black movie.
jwilliams 13y ago
My tips reflect my attitude more than general advice, but here goes: - Decide what you want out of the interview. How do you decide to work for this company? An interview is a two-way street. Engage with the interviewer, connect with the culture. Push back (a little) on their ideas, see what happens. - I hate puzzles. I think they're junk and have never found them to be good predictors (for either party). I usually (1) parlay it into some relevant experience "I encountered something like that when I..." or (2) describe how I'd solve a problem rather than dig into it [1]. - Demonstrate your common sense, flexibility, good social skills. Talk about how you work in a team. Talk about what you do when you encounter a problem you can't solve yourself. Talk about any self-lead learning you do. You need to fit in and you need the company to demonstrate they want you to help. Even if the interviewers aren't aware of it, more often these form the lasting impression from an interview. [1] Long, long time ago I was asked to produce a "sort" implementation. So I drew a bubble-sort. When one of the interviewers was somewhat outraged by this, my reply was "I didn't have any constraints, so I optimized for maintainability." A bit cheeky perhaps, but worked in the context.
johnnymonster 13y ago
I really appreciate this article! So many people go to interviews and are obviously unprepared. The simple fact that a person is unprepared for the given task is an obvious show on their personality. This goes for just about anything, not just interviewing. Would you just walk into a test without going to class first? Would you try to fly a plane full of people without first being taught how? So why would you go to an interview without knowing whats expected. - Know that an interview is a 2 way street. Have questions to ask the interviewers, if they ask you silly algorithm questions, have them explain to you how they use those algorithms in the workplace. - Make sure the job your interviewing is a place you can fit into, not just the other way around. - If you don't know something they are asking, just be upfront and say you don't know it, then ask them what it is and how its used at their company. Take note of this for future interviews. - Don't let the interviewer lead the interview the entire time. - For those of you haters that don't like the B-list idea, you could ask your peers that work at other places to interview you. (Interesting idea for a startup? Mock interview company? :)
- hatu 13y ago
  I don't think this analogy makes sense. I HAVE flown professionally for 6 years and now I'm jumping through cargo-cult like hoops to show that to a new airline.
mcv 13y ago
I've never actually interviewed at a company that interviewed like this. Is this the usual way in the US?
- scottschulthess 13y ago
  Yep it's pretty common

78 points by wpnx 13y ago

"So you're interviewing at Google and lunch time comes around. Food is free so you eat way too much, especially carbs. Your post-lunch interview is a disaster since you have trouble focusing due to lethargy. True story." Ha... I might have chosen the wrong cafeteria, but to me the food was a disappointment during my Google interview. The veggies were way too hard, I didn't like tacos, some of the meat looked indecipherable, and I was fumbling as I wondered whether there was a line, or whether I was looking stupid. I kinda wished there was NO free lunch.

wpnx 13y ago
I think "free food" and "all you can eat" has the effect of making many people completely unreasonable in their eating habits. The cafeteria near the gift shop wasn't too bad. I appreciated the hospitality :)
aegiso 13y ago
I honestly can't tell whether the last sentence was intended to be a punchline or not. But if so, good job!

justinsteele 13y ago

The idea of using "B-list" companies makes me a bit disgusted honestly. Have we put ourselves on such pedestals that we use other people's valuable time as unknowing practice runs? I would never interview somewhere I was not interested in working.

wpnx 13y ago
I think disgusting is a bit strong of a term. The same logic can be used when applying to college (a very similar process). You apply to a bunch of schools, some of which you don't want to go to. If you have your heart set on Stanford and you don't get in, you still need to go to college somewhere. I guess the advantage of interviewing at companies that at first glance you wouldn't want to work at, means that sometimes you get convinced by talking to the great people there. I've joined at least one company that wasn't initially my first choice for this exact reason.
- yardie 13y ago
  Maybe it's different elsewhere but every college I applied to I wanted to go to. Between the essays, interviews, application fees, and entry requirements I wouldn't waste my time applying to a place I didn't want to get in to. I've also cut an interview short once I realized it was a waste of time (H1b formality). If I'm not being taken seriously I won't take them seriously and I certainly won't waste my energy on fizzbuzz questions.
siegecraft 13y ago
Why not? Companies certainly have no problem interviewing B-list candidates.
- cbr 13y ago
  Companies do not, just for practice, interview people they have no intention of hiring.
  - vonmoltke 13y ago
    Not for practice, but companies do interview people they have no intention of hiring in order to fulfil internal policies or improve diversity metrics.
    - jjoonathan 13y ago
      Don't forget H-1Bs!
  - johnnymonster 13y ago
    yea your just flat wrong.
  - ajuc 13y ago
    Why no salary range on job offers then?
jjoonathan 13y ago
I can think of three reasons for interviewing at a "B-list" company that have nothing to do with putting oneself on a pedestal. 1) You might actually like the work/environment/personal growth opportunities/company health at the "B-list" company once you see it in person. Admit it: your initial classification involved a healthy amount of guesswork and is probably not fantastically accurate. 2) A stupid mistake in your A-list interview hurts both you and the A-list company, potentially dramatically so. You help both them and yourself by practicing. 3) Your increased bargaining power decreases the chance the A-list company lowballs your salary, shooting both you and themselves in the foot (hiring your replacement is expensive, lost productivity due to dissatisfaction is expensive, envy-poisoned work relationships are expensive).
- RougeFemme 13y ago
  I understand how a mistake in an A-list interview hurts you, but how does it hurt the A-list company?
  - johnnymonster 13y ago
    Because coming into an interview with your A-list unprepared is a waste of their time.
  - jjoonathan 13y ago
    Because it artificially reduces the talent pool they're drawing from. They might wind up hiring someone less competent who was better at signalling or making concessions to someone who wasn't as far ahead of the pack as they thought based on interview performance. Time and opportunity cost also factor in, of course.
ritchiea 13y ago
I don't think it's disgusting at all, I've known many people (not just developers) who do "trial" interviews before they apply to their A-list companies. Interviewing is a skill and if you don't practice it you won't be at your best when it's most important to you. That said, I recommend keeping your ears open and earnestly assessing whether the company may be a good fit even if it's on your "B-list".
ajuc 13y ago
If a company doesn't specify salary range in a job offer it's asking for trial runs to be honest. And most don't.

mountaineer 13y ago

There are some good tips and links here, but I don't understand the "hacking" metaphor. There are no big secrets. It all comes down to the "always be coding" idea that was presented a few months ago [1]. It just takes discipline and time-management. Succeed at that and many offers will come your way. [1] https://medium.com/tech-talk/d5f8051afce2 https://medium.com/tech-talk/d5f8051afce2

wpnx 13y ago
Great article :) Maybe not secrets, but lessons learned from the current state of the industry. Each one of the points I make is either from a mistake made in an interview I've personally given or received.
suyash 13y ago
Exactly, the article offers no new insights and the title is mis-represented. It has just listed what we assume we need to do in order to practice for the technical interview. Nice refresher though and I like that every thing is listed out for you.
rtfeldman 13y ago
The article's thesis is basically the exact opposite of this. It states in no uncertain terms that "always be coding" is wrong. That you should instead spend your time practicing techniques you never use when creating actual software, and that you should also maximize your interview count for salary leverage. "A lot of what I'm suggesting to do is pretty extreme. A lot of the skills here are not something you learn by doing a standard software engineering job (or get coming out of college). It's especially hard for more senior engineers to do technical interviews since most have limited time due to familial obligations and haven't taken CS 101 for quite some time."

DigitalSea 13y ago

I am completely against written tests or questions that ask abstract questions and ask you to write algorithms. Unless you're going for a position that requires a PhD in computer science and your job will be writing algorithms and solving overly complex problems, the pen and whiteboard approach just doesn't work in 2013. Hiring a developer shouldn't be as complicated as some companies make it out to be. Maybe for the likes of Google it has to be a lot more complex than others because they have an image and large workforce that depends on people being excellent self-managers and workers that require minimal management. For smaller companies you are wasting your time and my time asking me questions that test my ability to remember things more-so than they do to search and find answers. Lets face it, most developers these days are hackers. I've never met a developer who knows the answer to everything, I've seen the best of the best using Stackoverflow to find an answer to their question. The difference between a good developer and a great developer is knowing a little and for the stuff you don't know, knowing exactly what to Google when you encounter a problem you can't solve off of the top of your head. As Albert Einstein famously said, "Never Memorize What You Can Look Up in a Book" — that doesn't mean don't learn anything, but get the basics down and eventually you'll know what to Google when you don't know something. The real test of any developer is if they're a good fit for your team, have good work ethic and can get the job done. You can find the smartest developer in the world but they might not be a good fit for your team. Culture matters as does a good work environment with compatible people. The best way to test a developer anywhere in the world is to give them access to a computer, an IDE and their environment of choice. Then ask them to build you something. Don't ask them to write binary search code if they're being interviewed for a front-end position, ask them to build something. Welcome to your interview; build us a blog, build us a todo app, write a simple Wordpress plugin, write a jQuery plugin or what my current employer did: they brought me in for a trial for a couple of days (paid) and asked me to get my hands dirty on a real project they were currently working on. Just threw me in the deep end and after two days they had a good idea how I worked and if I was a fit.

wpnx 13y ago
> Don't ask them to write binary search code if they're being interviewed for a front-end position, ask them to build something. +1! Thanks for the thoughtful response; I really love the way you worded this. I agree with what you're saying; the best, most fun, challenging and fair interviews I've had have been at small companies coding side by side with somone. I wonder if it's possible to scale the "build-it" interview up to a google sized org. Another idea I've been mulling around is hiring people for an N month contract position where you get to work with them. If at the end, both parties agree its a good fit, then proceed. I can see a lot of pit falls to this approach, but it might work really well for people with strong referrals.

yanilkr 13y ago

The talk about tech interviews reminds me of this clip. http://www.youtube.com/watch?v=OXRi28W-ENY http://www.youtube.com/watch?v=OXRi28W-ENY

WalterGR 13y ago
The above link is to the first minute and a half of the interview sequence in the original Men in Black movie.

jwilliams 13y ago

My tips reflect my attitude more than general advice, but here goes: - Decide what you want out of the interview. How do you decide to work for this company? An interview is a two-way street. Engage with the interviewer, connect with the culture. Push back (a little) on their ideas, see what happens. - I hate puzzles. I think they're junk and have never found them to be good predictors (for either party). I usually (1) parlay it into some relevant experience "I encountered something like that when I..." or (2) describe how I'd solve a problem rather than dig into it [1]. - Demonstrate your common sense, flexibility, good social skills. Talk about how you work in a team. Talk about what you do when you encounter a problem you can't solve yourself. Talk about any self-lead learning you do. You need to fit in and you need the company to demonstrate they want you to help. Even if the interviewers aren't aware of it, more often these form the lasting impression from an interview. [1] Long, long time ago I was asked to produce a "sort" implementation. So I drew a bubble-sort. When one of the interviewers was somewhat outraged by this, my reply was "I didn't have any constraints, so I optimized for maintainability." A bit cheeky perhaps, but worked in the context.

johnnymonster 13y ago

I really appreciate this article! So many people go to interviews and are obviously unprepared. The simple fact that a person is unprepared for the given task is an obvious show on their personality. This goes for just about anything, not just interviewing. Would you just walk into a test without going to class first? Would you try to fly a plane full of people without first being taught how? So why would you go to an interview without knowing whats expected. - Know that an interview is a 2 way street. Have questions to ask the interviewers, if they ask you silly algorithm questions, have them explain to you how they use those algorithms in the workplace. - Make sure the job your interviewing is a place you can fit into, not just the other way around. - If you don't know something they are asking, just be upfront and say you don't know it, then ask them what it is and how its used at their company. Take note of this for future interviews. - Don't let the interviewer lead the interview the entire time. - For those of you haters that don't like the B-list idea, you could ask your peers that work at other places to interview you. (Interesting idea for a startup? Mock interview company? :)

hatu 13y ago
I don't think this analogy makes sense. I HAVE flown professionally for 6 years and now I'm jumping through cargo-cult like hoops to show that to a new airline.

mcv 13y ago

I've never actually interviewed at a company that interviewed like this. Is this the usual way in the US?

scottschulthess 13y ago
Yep it's pretty common