Stanford CS9: Problem-Solving for the CS Technical Interview

https://web.stanford.edu/class/cs9/

by master_yoda_1 • 9 years ago

440 286 9 years ago

web.stanford.edu

oneplane• 9 years ago

Maybe it's just me, but this seems to either miss the point of a CS interview, or makes a point about CS interviews containing pointless parts making them trivial. If an interview contains a known set of possible questions and you simply remember the answers, than in the end the whole exercise is somewhat pointless, isn't it?

pkaye• 9 years ago

Yes you are right. This is why I take some standard problems but change things a little bit so they have to think a bit. And I ask additional questions like how would you test this function, how to change improve performance, etc.

ubernostrum2• 9 years ago

Yes. People who claim that typical interview processes test "coding" or "CS fundamentals" or "algorithmic thinking" or whatever basically have to face the fact that they've really been testing for a set of skills that's different from what's needed by a working programmer. If they were testing for the actual skills of a programmer, there wouldn't be a cottage industry of books and classes and training materials to learn how to do "interview coding".

czardoz2• 9 years ago

This is what I was afraid of. I always thought interviews were something where you present your abilities, experience and knowledge. It should not be something you "prepare" for because then you're not showing off your skills, instead you're just regurgitating what you are trained to do.

I do somewhat blame the whiteboard culture, but I guess that's the one that has given the best results so far. I've no doubt that it will change soon.

Rebelgecko• 9 years ago

The idea of having a whole class on how to solve interview whiteboard problems (a skill that is, at least where I work, not very relevant to doing your job) is terrifying.

electricslpnsld• 9 years ago

This isn't that far removed from an algorithms or data structures class, or what you would learn in one of those programming olympics type prep courses that people do.

mathattack• 9 years ago

It’s 1 pass/fail credit out of 180 to graduate. The course looks as much like how to job hunt as anything else. (Resume writing, etc)

bitL8• 9 years ago

It's nothing new when it comes to competitive programming, which whiteboard interviews are just watered-down versions of. Russian/EE/Chinese universities are doing that for ages:

https://www.edx.org/course/how-win-coding-competitions-secre...

wyclif• 9 years ago

The idea that you now need to take a class to learn how to successfully interview with tech companies in order to prepare for interviews is terrifying.

BHSPitMonkey• 9 years ago

At Google, the recruiter who schedules your interview specifically recommends reading books written about passing Google's interviews. It's a little unbelievable.

jswizzy• 9 years ago

I actually had a job where it was relevant. Solving whiteboard problems is half the job of a nuclear field operator. I had to do boards with the captain of the ship, senior enlisted, and the reactor officer to qualify watch stations. The other half of the job is cleaning bilges till you make first class or weasel your way into an office job. It's not a fun job by any means but it paid for my College so I could do something I enjoy, Computer Science.

brailsafe2• 9 years ago

FWIW, preparing for interviews is standard practice irrespective of the industry.

NTDF93• 9 years ago

> FWIW, preparing for interviews is standard practice irrespective of the industry.

Industry is sane. They ask stuff relevant to actual work or real basics. They don't make a gameable process full of rules and techniques.

sidlls10• 9 years ago

Depends on what you mean by "preparing". There isn't another engineering industry I can think of where an engineer with more than a couple of years of experience is going to be asked to whiteboard this sort of crap. I mean, my aerospace engineer friends don't have to prepare by reviewing their PDE, vector calculus, and linear algebra classes, which is what the analog to programming interviews of this sort would be.

firstplacelast• 9 years ago

Sister is a travel nurse. She does not prepare for interviews and typically has several a year. Her entire interview process goes: call the agency and tell them she is looking for a new position, have one to several 30-45minute phone calls with hiring managers at the hospitals she is interested in (she actually took one once in the middle of a wine tasting - and got the job), then wait to hear back.

That's what it's like for many other in-demand and well paying industries (she's mid-20's and makes low six figures in San Jose). Stop pretending like everyone else has to deal with the same bullshit as you, hiring in tech is BROKEN. Other industries do it better.

People's lives are dependent on how well she does her job. Are the hoops you have to jump through justifiable for how "important" your job is?

jnbiche2• 9 years ago

FWIW, preparing for interviews is standard practice irrespective of the industry.

This is simply wrong. I suppose if you've spent your whole life as a developer, it may seem like it would be done likewise other industries, but it's not the case.

Typically, how you might "prepare" for interviews in other industries is...learning about your potential employer. And maybe reviewing your accomplishments. That's it. And most people don't even do those things. None of this hours and hours reviewing textbooks from your college classes, since you've been in the same job for 5 or 7 years and have forgotten algorithms that you never use in your job. It's simply perverse.

Software development is the only industry I'm aware in which technical preparation for job interviews is not only advisable, but increasingly necessary for interviews at all levels of the career hierarchy.

Even in other engineering disciplines, this kind of bullshit is unheard of for any interviews except maybe your first interview out of college. And in industries like law, medicine, etc., if a potential employer asked you to perform some random task from a highly technical and complex subject from med school or law school, it would be very unusual.

lr4444lr3• 9 years ago

I think the OP is implying through that this is creeping into top American university curricula. Having a Stanford degree in Comp. Sci. should correlate with interviewing success at relevant job openings for new graduates. This kind of "teaching to the test" and time spent on "job preparedness" is typical of community colleges and trade schools. They serve an important function, but it's distinct from the mission of a place like Stanford. As for the other aspects of job hunting school's career service department can and should handle the soft skills and referrals.

booleandilemma• 9 years ago

Is there any other industry where it's common practice to give job seekers homework during an interview?

Or to have job seekers complete an online test proving their skills?

https://www.indeed.com/forum/gen/Job-Interviews/Has-anyone-h...

ubernostrum2• 9 years ago

Not quite in the way it is in this industry.

What is unusual is that we essentially ask people to set aside and forget everything they know about how to do their jobs, and instead perform a separate set of skills which, since they are't used on the job, must be carefully re-acquired whenever it's time to go interview.

No other industry I'm aware of does that.

quotheth2• 9 years ago

Why should interviews test your ability to solve a problem you never expected to have to solve, rather than test your ability to prepare, research, and teach yourself?

sjg0077• 9 years ago

One can argue that this is the same thing.

sjg0077• 9 years ago

Good interviews involve problem solving from first principles. In CS it is mostly algorithms. Maybe some systems design and/or os and network fundamentals.

That being said, to prep is better than to not prep.. just like the SAT. The problem is that these things favor those who make the time.

Blazespinnaker4• 9 years ago

Preparation is a huuuuuuge part of being successful in the workplace[1]. Simply showing up just doesn’t cut it.

Part of interviews aren’t even testing skills, but testing prep. Of course, you want to test for innate genetic talent as well.

Good interviews do that, but as with gattaca, we see that desire and sincere interest counts too over genes.

Preparation, sincerity, and genes. That’s what I like to see in potential employee, in that order.

Sometimes, of course, one attribute really outshines the others - but its order in priority should always be factored in.

1. Source: individual who tried just showing up for 75% of his 20 year career.

jasonlotito3• 9 years ago

Sure. But at work, I know what I need to prepare for. Interviews don't exactly give you the questions ahead of time allowing you to prepare. So, preparation is not something they are testing for.

closeparen9• 9 years ago

Software engineering does not consist of preparing for and then giving short/intense performances.

Plenty of fields do - performing arts, film, trading, etc. all involve some form of short, intense, expensive activity to which you show up prepared and work in a burst of superhuman activity. But software isn’t like that at all - you get a problem and you dig into it, mull it over, research, etc. at your leisure until it’s done. We’re novelists, not actors.

sulam2• 9 years ago

The idea of screening for a software engineering gene is patently absurd. In an ideal scenario, we screen for the ability to do the work the job requires. In the normal scenario, we screen for some mix of that and the ability to apply cookie-cutter techniques to (hopefully) novel problems in the space of ~45 minutes. Some companies also ask you to do a sample practical problem either on site or on your own time. None of this indicates anything about someone's "innate genetic talent", if there is any such thing.

qwerty4561275• 9 years ago

The reality is the majority of tech interviews today are filled with questions/tasks that have little or nothing to do with the actual job you are going to be assigned. In fact an average programmer doesn't actually need to know a single piece of computer science or math (almost all such stuff is abstracted by common libraries and frameworks, whatever is not can be looked up on demand) nor to memorize anything (thanks to auto-completion and all the docs and Q&As being just a couple of clicks away), let alone to have skills in solving puzzles. Yet every other interviewer will ask you to write code on paper and give you puzzles on computer science, physics and everything. They will also ask you about your previous salary and the reason you have left the previous job (both matters are purely private IMHO), why have you chosen them (ridiculous, I just want to earn living in a sound company and have sent the CV to a number of companies to land the first one that feels fine and wants me), what do you want to achieve in n years (never thought about this, just want a job) etc. And a funny thing: a friend of mine (an experienced developer with history in multinationals) has once told me he was rejected told being "too unsociable", "talking too little" which is the perfect opposite of what he actually is (dozens of his friends would undoubtedly confirm). Puzzles are fun, intelligence is reasonable to be benchmarked, nevertheless the interviewing thing is done at least slightly wrong usually IMHO. I just hope some scientific research is going to emerge in this area in near future to help rationalize the hiring process. As for myself I ask nothing but the candidate's opinion on some relevant subjects (the opinion itself doesn't really matter much but it can indicate certain degrees of awareness, understanding, intelligence and motivation, also the talk can somewhat demonstrate the personality) and their GitHub profile.

flor1s• 9 years ago

I don't think these kind of coding interviews are given to average programmers though, and if they are I'm sure they are taken with a pinch of salt (or with a lot of help from the recruiter, or using simple tasks such as FizzBuzz [1]).

In my experience, having been an average programmer (and maybe still being, I hope that by now I'm at least slightly above average) who worked in The Netherlands at a "system integrator", a web dev "sweat shop" (some projects using 10 year old tech, relatively high staff turnover) and even a startup, such companies don't ask for whiteboard coding, however take home projects are quite common.

I also interviewed at some more "hot" unicorns in Japan, which do have these kind of questions (using a dehumanizing online test in fact).

1: http://wiki.c2.com/?FizzBuzzTest

bitL8• 9 years ago

It's a fitness test. Are you going to bring me value, or are you on the verge of burnout with outdated skills, trying to live off your past? "What did you do for me today?" is what matters for company to stay afloat and brutal competition is the way to achieve it. What kind of society it creates is another question.

virgilp4• 9 years ago

and their GitHub profile.

I have nothing in my GitHub profile. Some toy repos of no particular significance, one contribution to Rust that I've made before realizing it takes too much of my spare time... and that's it. I don't think that should make me un-hireable ... people that have kids tend to not have much spare time besides work, learning new stuff to stay relevant, and taking care of said kids. Not to mention, my company has me going through some bureaucratic process for any sort of open-source contribution that I intend to make.

expertentipp5• 9 years ago

You want too see public projects on my github profile? I'll work on my public projects during office hours, deal? There are companies which become hysteric on the mere mentioning of the words "public", "open source", and "GPL" and doing it, while already employed, will undoubtedly initiate multiple meetings with a bunch of security and legal guys staring judgmentally at you. I hope such companies are more forgiving when candidate has no public github/gitlab/bitbucket.

dietr1ch2• 9 years ago

I think it's rather silly to "prepare" for an interview, but IMHO what they expect at Google/Facebook/Amazon/Microsoft is not something you should really need to prepare for if you took the time to really understand the algorithms and general techniques you study as a CS undergrad.

Rehearsing at a relaxed pace over a single weekend should be more than enough, particularly to get used to discuss your ideas and using a whiteboard.

ng12• 9 years ago

I completely agree. Every time I start a job search I dust off my copy of "Cracking the Coding Interview", do a half dozen problems on HackerRank and I'm good to go. Sure, it's not exactly the skillset a professional software engineer needs -- but if you're a professional software engineer it really shouldn't be that hard.

czardoz2• 9 years ago

You're absolutely right. The problem with these kinds of courses is that you will now be competing with people who have been specifically taught how to prepare for and crack technical interviews.

I am pretty sure that they will perform better than people who just spend a single weekend rehearsing.

deepGem• 9 years ago

Wholeheartedly agree. These companies most likely are trying t o understand the 'why' behind your algorithm choices. Of course, there are exceptions but largely this is the case. Understanding the why only comes to you, if you really understand the algorithms and are able to map those algorithms to use cases.

akhilcacharya4• 9 years ago

Either I’m a bad student or you have an inherent ability that I don’t have. I’ve interviewed at all of those companies and you need a lot more than a weekend to succeed - even my friends with offers took more time to study than that!

ianamartin2• 9 years ago

One of the things I miss about being an orchestral musician is that you always knew what you were getting into when you went into an audition. You've known the pool of excerpts for your instrument since you were in college; you've been working on them for years; you've probably known the excerpts for this particular audition for months if not a year.

Every one of them is the same: you go in behind a screen, and you have to play those few minutes of music better than anyone else that day. It's hard to do because they choose the hardest stuff, but you know what you're up against.

It's very imperfect. It doesn't reflect most of what you're going to be doing in the job. You might play one of those pieces in a given season. The bulk of your time is spent listening to the players around you and playing in sync with them, understanding what the conductor wants, etc. There's a lot more to being a good orchestral musician than being able to nail your part for Don Juan completely alone without context.

It's not great, but it is consistent. Evert tech interview I've had in person has been wildly different. Even since I learned pretty early on to ask about the process. You still have no idea. It can be anything from an entire dev team grilling each other in a pissing match that had almost nothing to do with me, to 1:1 with someone grilling me about the finer points of a PhD topic they just finished years studying to a casual conversation over coffee just to get to know you to live coding exercises where you have an hour to write a 3-d car driving game to a conversation with part of the team where they tell you about their real-world problems and ask you for ideas about solutions to getting paid to work on a live project. All for web developer or data engineering positions.

I remember being in one interviewer role a while back for a dev ops person for the team. I got thrown into the mix at the last minute because the other interviewers realized the day of the interview that they don't know anything about dev ops, and I kind of carried that portion of things for us. They had literally nothing to offer to the conversation, so it was unprepared me interviewing a highly competent dev ops pro. After 20 minutes, the other interviewers left and said, "I really don't know why we're here. I don't understand any of the words either one of you are using, so just carry on without us."

I felt really bad for that guy. He was really really good, and the only thing we got out of it was that the team didn't know why we were hiring for that position.

The amount of variability is truly insane. I hope that whiteboarding culture doesn't win the standardization contest because even worse than in the case of a violin audition, there really should be no performing or bravado in an engineering team.

But even standardizing around that would be an improvement over the utter chaos right now. Because then it's consistent. Perhaps misplaced, but at least consistent.

I wish that instead of teaching classes about how to win the CS technical interview, schools would teach classes about how to interview for technical roles. How to design effective interviews that will help find the best person for that role. There's a ton of research around this. It's not just "whatever seems to work for us." And we need to be better.

mratzloff• 9 years ago

I wish that instead of teaching classes about how to win the CS technical interview, schools would teach classes about how to interview for technical roles.

Aside from security, I think this is the biggest challenge we face as an industry. Everyone interviews differently and almost all are done poorly. But the vast majority think they are good interviewers, and they're just not. It also won't improve on its own, because there's almost never any effort at honestly evaluating the hiring practices or decisions.

jmtame• 9 years ago

It’s mostly a copycat culture. But the best companies today are getting smarter and using more realistic interview techniques that accurately reflect the work.

I’m also working on the space with www.onsites.co to solve how broken the interview experience is.

profalseidol• 9 years ago

I blame the limited time that Capitalism provides. Every minute you use when interviewing is capital being used up. Capital that needs to grow.

kulu20023• 9 years ago

Till today I haven't asked anyone to write actual code on whiteboard. Recently I had a chance to interview a Stanford grad who had previously worked on embedded sys in some start-up. I asked him to draw system level architecture of his product in OSI layer format like where HAL/ firmware, RTOS, insys mem, db, application, UI are placed and how they are communicating with each other ...and this guy was staring at me like I am asking him to jump down from 10th floor. Then I thought did I do something wrong... I mean if you have really worked on/experienced something then you should know that thing thoroughly and then you don't need any special prep for interviews

_xczx• 9 years ago

I've never felt comfortable answering questions like those, because the designs are owned by the business. Even if I made it, I don't feel like I have the right to hand a design for my current employer to my next employer.

scardine• 9 years ago

Set up any system with money rewards and people will game it.

internetman55• 9 years ago

1 credit is about 60-80hrs max of study right? Seems reasonable to spend that much time preparing for tech interviews if you wanna go into my field. My friends who weren't smart and too lazy to put in effort spent that much probably

adamnemecek2• 9 years ago

I know this has been said a billion times but the CS interview is bullshit. It's like asking a pianist to describe how they would play a composition on the white board.

I always thought that this is a good question to ask https://github.com/alex/what-happens-when but then again probably not for all roles. It's good because even if the interviewee has seen the question, you can really gauge how much they know.

nnd• 9 years ago

Still very gameable, and only test domain knowledge, rather than problem-solving skills.

cat199• 9 years ago

If a stanford CS degree doesn't otherwise prepare students properly for a tech interview, I'm going to wager it is the interview process that has a problem, not the stanford CS degree..

adamnemecek2• 9 years ago

You are right but like just having to use the fucking white board is different enough to throw people off.

jdiaz55132• 9 years ago

This makes me very, very sad.

I will never subject one of my potential hires to this nonsense. These concepts are valuable and academically interesting, for sure, but for the practical kind of engineering that's done at most companies it's simply not needed. Either that or it's already implemented in a library.

What a waste of time.

akhilcacharya4• 9 years ago

I'm sympathetic to this viewpoint but looking at the cost/benefit for a Stanford student I think the benefit to studying for these interviews is clear - its a bit of a simplification, but for Facebook if you can do 3-6 problems over the course of 2 60 minute internship interviews you have the ability to get a $75k-$100k signing bonus if you convert to full time in addition to more shares over 4 years. Granted this depends on whether you're a high performer during the internship but I definitely understand why someone would make or take this class.

sidlls10• 9 years ago

I recently got a promotion to management. I have different responsibilities, but I get paid more and have more influence over solutions to interesting engineering and technical problems. This role feels even more like what my engineer friends in real engineering disciplines do than my role as Lead did: leverage their education and experience to solve complex, large scale problems. These interviews are good at testing for jobs in software that have as an analog jobs in real engineering equivalent disciplines consisting of computing CRC integrals by hand all day.

What I'm saying is: unless these students just want to sit around repeating their DS&A course(s) over and over again the rest of their lives, this sort of interview, job, and prep course is counterproductive in the long term.

bearforcenine10• 9 years ago

It's very tempting to say this. However, trying to find an alternative that is not equally or more gameable is very challenging.

Take home assignments are easy to cheat on and take a lot of time.

Asking questions about someone's experience is a great way to find someone who is a great conversationalist that can't code.

Asking someone to program at a computer in a limited amount of time falls victim to the same issues that the competitive programming, whiteboard interviews currently do.

sidlls10• 9 years ago

Take home assignments are easy to cheat on? What does that mean (in the context of a take-home problem as an interview method)? Are candidates expected to derive solutions to coding or engineering problems themselves from first principles as their day to day? The answer is "no" almost without exception, even in serious research or hard core low level systems programming jobs.

clarry3• 9 years ago

Take home assignments can take little time or a lot of time. Interviews that consist of round after round after round after a bunch of phone calls take a lot of time too. I actually prefer a home assignment of similar length.

I don't believe cheating is such a major concern. The applicant should be able to talk about their solution and all the choices they made if they actually wrote it and understand the solution.

akhilcacharya4• 9 years ago

I've been through the ringer quite a few times now (though less than the average Stanford student) and I think about these interviews more than I probably should just for my sanity.

This is a decent primer (and people need primers!) and a good resource overall but I'm very skeptical that this is terribly helpful for most interviews. I liked some of the problems but most are about a notch lower in difficulty than required for the offers Stanford students get.

With that said, it's clear that the students that take this class are going to do well in their internship and job search. I'm honestly just becoming more convinced that ability to perform in these interviews is an inherent quality of top students (no matter the original field!) at this point.

andoma2• 9 years ago

FWIW the second example of finding halfway points in https://web.stanford.edu/class/cs9/sample_probs/ListShufflin... is buggy. Crashes if the list have odd number of elements.

stephencanon• 9 years ago

"Your job is to write a function that accepts as input a pointer to a linked list with an even number of elements"

andoma2• 9 years ago

Fair enough :-) I'll read more thorough next time.

cabaalis• 9 years ago

Would writing it to handle odd numbers of elements as well cause the employer to move forward with a different candidate?

kjgkjhfkjf• 9 years ago

Two more of my favorite interview questions rendered useless :C

lz4003• 9 years ago

I think this is terrible. I feel there are many good engineers that can't possibly compete for decent jobs in tech companies because they haven't spent 6-12 months reading cracking the code interview, doing this Stanford course, practicing mock interviews in crowdsourced websites, getting their leetcode rank up, attending bootcamps where they pad their githubs and practicing any single interview question they can scrub off glassdoor. All things that are marginally useful in the job at hand. And this is getting worse all the time.

twblalock• 9 years ago

It's really not that hard. I suppose there might be a few companies with insane expectations, but most interviews don't require that level of preparation.

lz4003• 9 years ago

I don't know. If all the candidates are that well prepared, then if you are not you are at a disadvantage, even if it didn't used to require it. And at companies where people want to work for, like Google/amazon/FB/Netflix, etc. and startups many people come prepared.

shagie4• 9 years ago

I work in the public sector. There is a very strong "this must be fair to all applicants" bend. The same criteria is used for all applications - in particular, the exact same questions.

As part of the application, I was instructed to provide 2-3 paragraphs on each of half a dozen questions that covered various aspects of software engineering. The in person interview asked a predefined set of questions about the material that I had provided. That part was more of a "demonstrate that you have the mastery of the material claimed in the written portion and that it wasn't produced by someone else or some other source". This also tested communication skills.

No weight was given to GitHub contributions, hacker rank, leetecode rank or whatnot. There was no whiteboard.

While this isn't a fabulous job at a tech company, it is one where good engineers can and do find themselves at without needing to have the proper shibboleth to get into one of those tech companies.

For another job application that was more of a sysadmin/programmer bend, a simple backup script was the assignment (took about 1h to get all of the edge cases). A portion of the interview was a demonstration and review of the code (in which I had to answer questions about the code that I had written).

While mock interviews can be helpful in the communication skills department and reducing anxiety, there are many other ways to test the person rather than use a proxy such as contributions to a public repository or foo rank websites... and also without resorting to whiteboard for various algorithmic tricks that you either know or don't know.

sjg0077• 9 years ago

Stanford kids do well on the SATs which require similar prep. Same thing, different day.

thaumasiotes6• 9 years ago

The SATs are specifically designed to meet these goals, among others:

- Preparation not required.

- Preparation not beneficial.

And it shouldn't be surprising that they achieve that well. Consider these scatterplots comparing students who took the SAT without preparation to students who prepped: https://infoproc.blogspot.com/2012/02/test-preparation-and-s... .

As further described at the same link, research quite consistently shows that the effect of preparation on SAT scores is small, and...

One of the most remarkable aspects of this line of research has been the lack of impact it has had on the public consciousness.

Again, this shouldn't surprise you, because it is a design goal of the SATs not to show an effect of preparation on scores, and they do their own research to ensure that preparation in fact does not have much of an effect.

bitL8• 9 years ago

All you mentioned still might not be sufficient if people don't like working with you or if you are so good that interviewers feel threatened by you regarding their future career prospects if they let you in. Happens all the time.

pnw_hazor2• 9 years ago

It is a filter to identify compliant boot-licker types.

Normies and free thinkers just take a pass.

However, golden wingless dragons seem to do just fine.

starchild_3001• 9 years ago

I kinda like the idea of having an intense data structures and algorithms class for hands-on problem solving.

If a candidate has shown an ability to solve several hundred medium+ DS & Algo questions on the spot, that gives him an edge up in day to day to programming. Not everybody can do that.

You can supplement that with other areas (concurrency; distributed systems; execution latency, memory management etc; quirks of and design ideas behind your favorite programming language).

I think this class can be a good prep for day to day programming.

SmirkingRevenge4• 9 years ago

I hate the interviews as much as anybody... but really I wish that kind of instruction had been a bigger part of my college curriculum. Yea, we had data structures classes, algorithm classes - but none of them really made me good at any of them. Not like how math classes makes you good at the math, by forcing you to solve problems over and over, until it becomes nearly instinctual.

I've actually become a better programmer by practicing interview problems, because they ultimately are a bit like the arithmetic involved in solving more large scale problems.

yeukhon2• 9 years ago

Yeah, I agree on the last part. Practice helps. Memorizing solution doesn't. It takes effort to crack those Leetcode problems.

foobaw• 9 years ago

Don't programming bootcamp classes do this kind of thing too? I feel like this just increases the probability for a student to do well on the interview. If you read their intro slide, it clearly states "Level the playing field between applicants who may learn these things through informal mentoring in their friend network, and those who would otherwise not know this stuff"

It's kind of sad that there's a trick that needs to be learned to solve technical interviews without testing the candidates' inherent knowledge, but at the moment, this could seem like the most logical way to get a good job for a Stanford CS student with no knowledge on technical interviews.

FullMtlAlcoholc• 9 years ago

To everyone bemoaning the introduction of a class such as this, it's a 1 credit class, which at Stanford roughly translates to about 3hrs/week of work given that you're expected to take 15 credits per quarter. It is comparable to a class on financial responsibility or golf. Its focus isn't so much on how to crack a technical interview than it is on how to prepare for a job interview in general.

Mock interviews, resume writing and critiques, life at startups, how to answer team/behavioral questions, and panels of employers and employees are all covered with sample whiteboard/coding problems only being given one week of attention. This is simply preparation for how to professionally navigate the job landscape.

NTDF93• 9 years ago

So, Stanford grads can't pass interviews without training for it. Looks like a degree is really worthless. Al that matters is memorizing these problems.

MollyR• 9 years ago

A whole class for technical interviews seems like overkill. It also gives me an uneasy feeling of being in a tech bubble.

bearforcenine10• 9 years ago

This kind of prep has been common place in other desirable fields for many years. Law, medicine, finance. They all have books, classes, etc. that you can take to prepare for interviewing, taking the bar, mcat, etc. Compared to college admissions, the CS interview process looks downright sane.

seanmcdirmid3• 9 years ago

They all have prep for everything but interviewing. An interview to get a residency or a junior assistant position will be much more about your credentials and a history of your performance.

watwut2• 9 years ago

If there is whole course on "interviewing", in or of top schools no less, then the interviews really became divorced from any meaning. That should be seen as major red flag that industry is doing something wrong.

Maybe there should not be cookie cutter interview at all, but more of harder look at which skills and personality traits are really needed for this or that position.

And I tend to do good on whiteboard interviews.

bb88• 9 years ago

I always thought the the technical white board interview never really matched what was expected.

A binary tree search has little to do with figuring out the pros and cons of which api to code against.

How about a scenario where you get to try to find a bug with legacy code?

davesque2• 9 years ago

The on-the-spot technical interview is the biggest waste of time in the history of humanity. Everyone underperforms in technical interviews. I've conducted a number of them and I've never learned a single thing other than the fact that people make surprising mistakes when under pressure in contrived situations. Here's something that I think works much better: come up with a novel challenge that requires a couple hours of honest effort and have candidates present their solution to you when they come in.

bearforcenine10• 9 years ago

How do you prevent cheating? Someone can very easily have a friend complete the challenge and walk them through it in a lot of detail. They could prep well enough that you hire someone who is massively under-qualified.

Then if your company is large enough, your novel challenge gets leaked and everyone knows it ahead of time. Solutions start being sold or distributed. Then your interview is meaningless.

I'm all for a viable alternative to the whiteboard interview, but I haven't encountered one yet.

davesque2• 9 years ago

If your challenge is novel, as I said, then it should be difficult for them to cheat. All the same, people are welcome to cheat. It should become clear that they've done so when you're interviewing them if you ask the right questions when they're explaining what they did. And if they somehow make it through anyway, you should be evaluating the quality of their work until they get established in your company. If they're underperforming over the first month, you should be showing them the door.

ztjio• 9 years ago

For anyone with any kind of reasonable background suggesting they can do the job, the alternative is simple: just give them the job on a probationary basis. Give 5 people the job, tell them one will keep it after a 3 month contract period. Choose the ones you want to keep.

Balgair• 9 years ago

I mean, as long as that person is getting their 'friend' to do the work while on the job, who cares?

Like, things get out on time and shipped, right? I may misunderstand the intent of the comment though.

But if they are sub-contracting out their work AND the work is done correctly, on time, etc. then it's all gravy. Yeah, you should probably hire that 'friend' instead, but if the interim works, it works (speaking very generally here)

mariopt• 9 years ago

What the hell?

Shouldn't we focus on creating great engineers instead of training them to make a good impression on an interview?

I think is completely immoral. Becoming good at something is a matter of consistent practice that brings experience and expertise over time. There is not other way around it.

People might pass the interview but their hat will fall in a matter of weeks. This is PUA for interviews by a University, this is really depressing.

The only thing that gives me hope is that great engineers will always solve problems no matter what. Tech hiring is going to become much harder.

ksml2• 9 years ago

This is a _single_ pass/no pass unit out of 180 required to graduate. Stanford absolutely focuses on creating great engineers (or computer scientists, for those more interested in the math or theory sides), but it still helps to have a small course pointing out tips and things to look for in the interviewing process.

quotheth2• 9 years ago

Say what you will about the state of the software dev interview, it sounds like it could be a fun class.

fecak• 9 years ago

I'm glad they are teaching students about resume writing, and hopefully the professors are versed in hiring outside academia. I write hundreds of resumes a year for my clients, and a high percentage of young clients are using really poor resumes when they engage my services.

It seems many new grads are being drawn to highly-visualized resumes with fancy templates, often featuring a bar graph for skills ranking (some ranking themselves as "8 out of 10 in JavaScript", which comes across as laughable and out of touch).

My feelings on memorizing data structures aside, the resume lessons may at least help some grads get interviews that they wouldn't have otherwise, and that's a good thing.

tw1010• 9 years ago

This is a natural response to the incentive structure that has evolved. But fear not, the fact that this metric is being overemphasized to this large a degree surely must mean that the adversarial species (the industry) will respond by changing their strategy. The more universities focus on vanity metrics (helping students build their peacock tail), the more likely it is that the industry realizes the kink in their armour and shifts to some wiser signaling measure.

tinokid2• 9 years ago

Could there be a clearer sign that the quality of higher education in our time is in steep decline?

If, one hundred years ago, Oxbridge had floated the idea of sanctioning a student to embark on a program of study designed to anticipate questions that might arise in a job interview, it would have been as preposterous as suggesting that the Queen should take her meals in a pub.

And yet today, we have one of the preeminent universities not just of the United States but of the world offering a course that appears to amount to Kaplan for a tech job.

bearforcenine10• 9 years ago

I doubt this is a sign of a decline in quality of higher ed, and more a sign of the popularity of CS as a major and software engineering as a career.

These kinds of courses and prep has existed in similarly popular fields for many yeas: law, medicine, finance, etc.

tinokid2• 9 years ago

1) Those are professional schools 2) Even so, no respectable law school offers a bar prep class. Nor does any med school offer "How to ace the USMLE".

UncleMeat2• 9 years ago

40 years ago, my mom took a one credit course in undergrad for her cs degree that was on resume writing, interviewing, and negotiation. Is this so different?

umanwizard• 9 years ago

Did your mom go to Stanford?

ksml2• 9 years ago

Oh, come on. I think you are exaggerating quite a bit here. This is a single pass/no pass unit out of 180 units required for graduation, and, as a Stanford CS student, I can assure you the other classes are extremely rigorous. I don't see a problem with a one-unit class designed to help build confidence and demonstrate your skills to an interviewer. If you think that such a class shouldn't be necessary, then blame the current interview system, not all of higher education. Higher education has its problems, but this is hardly grounds to claim it's in "steep decline."

Yhippa• 9 years ago

As crazy as these interviews are they have to be working right? Some people must be passing these things otherwise there would be a lot of unfilled positions.

So much for there being a staffing shortage in our field. These types of interviews imply there is a much higher bar that exists to weed out all the chaff due to oversupply or companies won't settle for anything less than the most academically best people.

seanmcdirmid3• 9 years ago

Not everyone is (or pays as well as) Google. Many companies don't have a bar as high, there is still a lot of work for B and C players to do (albeit, that is probably true even at Google).

expertentipp5• 9 years ago

Some people must be passing these things otherwise there would be a lot of unfilled positions.

The point is - there are a lot of unfilled positions. Companies notoriously complain for not being able to find "good" software specialists, because... people with minimal clue on how to judge relevant skills introduce increasingly more cut-throat filters and processalize everything.

adjkant• 9 years ago

My school does co-op's and has a 1 credit co-op prep course. We do have practice interviewing there. We also do resume workshops, general best practices for the industry you're in, etc.

You can do both the content and the prep, as I am sure is the case with Stanford CS.

While it's unique to have a course specifically named for this and am sad to see it as well, I don't think this is as big as people are making it out to be, nor is it a canary in the coal mine for higher education. To me, this only signifies the growing shift in education, as it becomes more available to all, being about preparing for your career as much as learning itself. The simple fact is that most attending college today are not doing so just out of the desire to learn alone, but also want to, well, have a nice career in their respective industry. To be able to make a living.

While I would also agree with cautioning about education for career alone, I think it's important that modern education focuses on both. It's the reality of an increasingly college educated world.

Eridrus• 9 years ago

Hey it could be worse, people could be getting a degree because they need it for signaling purposes and/or to satisfy an arbitrary immigration bureaucracy and don't actually need any of the things they're being taught. Oh, wait :)

keeptrying• 9 years ago

Institutionalzing a broken process. :-/

tentakull• 9 years ago

What a joke, but I'm completely unsurprised. Prep for the SAT, prep for jobs, prep on the job - minus the whizkids, Stanford grads make great corporate drones.

akhilcacharya4• 9 years ago

Corporate drones that are paid $50-$100k more than me total comp their first year, yes.

wbillingsley• 9 years ago

I know universities are sometimes accused of "teaching for the test" anyway, but, well, wowsers

methodin• 9 years ago

Not all jobs require this preparation-style. If you don't like it - shop around and find companies with different styles that match your preference. Interviews are equally important to the interviewee as the interviewer.

numbers• 9 years ago

The last two places I've interviewed and was turned away would have loved a "software engineer" who had taken this class. I am a typical developer, I can get shit done but there are rough edges I have because I'm human. I think, interviewing in general is tough for me and when there's a set way of showing your abilities comes up, I'm not great at presenting that.

My github is active, I work on things that a potential employer as well as fellow developers would be interested in and I also am trying to grow by showing bad, good, and some code that I'm very proud of on my github. But, the thing I noticed at the two aforementioned interviews was that they hadn't even taken a look at my github.

bitL8• 9 years ago

Just wait until you start interviewing at even crazier companies than FB/Google that would like you to tell them 20 ML algorithms, 20 computer vision algorithms, compare expected results of non-linear optimizations applied to some weird Deep Learning problem and analytically justify it (why is it worse/better than SGD on this loss function?), then off to some deep domain knowledge, conjure graph algorithms on the spot on problems you've never seen before, all in 1.5h, expecting Stanford/MIT PhD-level answers.

reallymental• 9 years ago

If you're interviewing at Deep Mind, sure.

optymizer• 9 years ago

Sharing a data point: I've interviewed with Google multiple times and at no point during the interview was I asked a question that required an ML/CV/DL algorithm.

I suspect those would be more appropriate for a 'data scientist' / 'researcher' position - for a generalist, the interviews were very standard and not crazy at all.

In hindsight, if I had taken the time to review basic CS algorithms ahead of the interview, I would have done much better.

That said, I'm not sure I'd be a better employee at Google if the only difference between my being hired or not hired is the fact that I reviewed some basic data structures and algorithms.

yigitdemirag• 9 years ago

“Most metrics are good until you start optimizing for any of them”

kramer14162• 9 years ago

Off-topic probably:

This timing!

I'm going to interview on Tuesday with a startup in SF. I've spent better part of last 3 weekends studying and solving DS&A.

Any advice from HN on what could I do in ~14 hours of prep time?

bitL8• 9 years ago

Do Codelab at Facebook, sleep, avoid jetlag.

sk2104• 9 years ago

I understand this encourages an imperfect system, but I would have really appreciated this as an undergraduate who didn't understand how interviews worked.

While the system is admittedly problematic, does it really come as a surprise that for extremely competitive jobs at the entry level, such artificial hurdles need to be used to filter the plethora of black-box applicants? I can't speak to more senior roles, but for entry-level, this only seems like a natural (and practical) response. It happens everywhere, not just CS:

For any competitive school admissions, SAT/LSAT/MCAT what-have-you are all poor indicators of student performance, and boil down to trainable tests.

In finance (both quant finance/and positions like sell side banking, private equity), people constantly practice math/financial modeling/accounting, for interviews. Many of the more selective quant shops (for undergrad hiring, I should mention) have much more difficult problems than MS/GOOG/AMZN technical interviews, and I would argue the type of competition level math/probability are just as unrelated to their jobs.

In management consulting, people spend hundreds of hours practicing for case study interviews. Just search consulting interview prep, and you'll find an egregious number of prep companies.

Some people brought up law and medicine. First, I don't think the grueling nature of the medicine certification is even close to what it takes to be an entry level developer. In law, while "technical" interviews are rare, often times employers filter you by much cruder means: pedigree (both the school you attend, and at top echelon law firms, clerkship status, and top-top grades within those schools). Is that any better?

The common denominator here is the high demand for all of these schools/jobs, and the problem always seems to come down to, how to optimally recruit -given- resource constraints. Maybe I'm cynical but almost any reasonable entry-level interview can be "gamed" or trained for, and most firms are either small and lack resources to extensively evaluate their applicants holistically, especially if they're only in undergrad, or they are large and get way too many applicants, so some proxy is necessary.

tzhenghao• 9 years ago

How is this conceptually different than a course that focuses on standardized tests like the SAT? Having worked for only almost 2 years after college graduation, I can still see that there are many more technical and non-technical skills that affect one's and his/her colleagues' performance on the job. Being nice and helpful is one. Constantly learning from mistakes and rapidly iterating while adding value to the team/company is another. More examples: Picking up technical books, writing toy projects to learn new languages/frameworks/libraries and being able to come up with good engineering decisions. The list goes on.

Not to be too salty about this, but I remember friends from college who are terrible teammates (no significant contributions to group projects, barely understanding the project material, but knowingly do so cause others will finish it for them etc.) but go on to get job offers from the Big Four. Having these technical whiteboard interviews will not filter for such soft skills that are needed to succeed in the workplace.

austenallred• 9 years ago

People measure what’s easy to measure, not what’s valuable.

abiox• 9 years ago

maybe a bit meta but i've been wondering why course links are posted to HN. is this a tradition or something?

pjmlp14• 9 years ago

This just feels wrong.

RafiZ• 9 years ago

As other commenters alluded, interviewing and coding are indeed two different skills. However, contrary to some of the comments, I don't think there is anything wrong with preparing for an interview or even taking an entire course for that matter. If it helps you shine and showcase your real skills to an employer then why not? I’ve seen many brilliant software engineers get rejected for positions cut out for them only because they were so nervous at interviews that they had trouble even understanding simple questions until right after the interview ended. I know that because I'm a co-founder at Pramp.com, a free p2p mock interviewing platform for software engineers. It's incredible to see the improvement in one's confidence even after a single practice interview.

sov• 9 years ago

Do people actually put "objective" on a resume? It seems laughably hackneyed. My experience is that something near 40% of people have it, and it usually is the most trite sentence possible.

paulus_magnus2• 9 years ago

Question from European side.

We hear there's a shortage of good people in SV / USA. What if you plainly ignored all companies that whiteboard? There should be plenty well paying jobs left.

disclaimer. a major tech company whiteboarded me twice (codility + live coding via google docs). They were really selective, none of my friends passed. In the end the job was lousy so ultimately the test selected more for willingness to jump through irrational hoops than productivity.

sigi45• 9 years ago

I trained for google and failed. Still it didn't feelt like stupid or a waste of time.

It was interessting to do so, i think it made me better and i will try it again.

And yes there are people who don't care enough to work for companies like google and there are.

Also while i did more interviews as the person who is interviewing: I feel that i like to have more better prepared people to interview.

Stanford CS9: Problem-Solving for the CS Technical Interview

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