The opt-out button: "I don't need more coding interview practice".
My first thought: Whoever designed this is super salty for me not wanting to provide my e-mail.
Out of all of the problems in my life, too much e-mail is certainly one of them. I like to keep it to a minimum. And as an adult, a weekly coding problem falls so down far on the priority list compared to all the other e-mail I'd get.
You've got a cool site and I appreciate all the hard work creating high quality content (I've looked at the free questions and considered subscribing a few times in the past). I think your business model/pricing could use work. Unless I'm mistaken and things are going well .. in that case, I'll withdraw to my cave :-p
My suggestion would be to have a slightly cheaper tier (probably no more than a hundred bucks). This mirrors the cost of two-to-three interview books. You could add a custom grading or personalized tutoring option for the full 500, or heck, even more (this is sort of like the GRE/GMAT prep option). Come to think of it .. I wonder why the GRE/GMAT prep crowd hasn't tackled programming interviews?
Thanks for the note. Definitely a great point. Not sure yet how we tier out our product, but tiered pricing is definitely the state of the art.
We've been working on some /tech/ to enable tiered pricing in the meantime. The Site's all custom, and so far there's no notion of a "product" yet...just "paid" and "unpaid."
Share your question re: where's Kaplan on this stuff!
Price seems expensive to me as well. In data science there is a similar site which has become pretty popular if you are interviewing in those top tech companies, but it is cheaper.
As the guy above was suggesting, that data science site does personalized feedback and that justifies the high price. Otherwise, the way it is now, it feels like it should be priced similarly to CTCI.
It's crazy that there is a whole industry dedicated to cheating ahem gaming job interviews in software/IT. Imagine if doctors or lawyers or real engineers did this. No wonder we can't get taken seriously as a profession.
Imagine if docs could be rejected from a new job because they failed to repeat the obscure diagnosis that was featured on the last episode of House, that really has nothing at all to do with the job they wanted to do.
Imagine if lawyers could be rejected for not being able to explain the minority opinion in Foobar v. Bazquux, which again, has absolutely nothing to do with their expected duties as prosecutor of poor people with small amounts of marijuana.
Imagine if real engineers were asked to build a suspension bridge out of silly putty, table salt, and carbon fiber.
The interviewees are simply doing their jobs, which is to analyze a problem and implement the most cost-effective solution. The interviewers are the ones causing the problem. Granted, it isn't always because they are non-technical people trying to gauge the value of skills they don't understand. A lot of times, it is because the interviewer is a tech person that still can't effectively gauge the value of skills they do understand, and also wants to look clever in front of a stranger, subtly discriminate to preserve "culture", and do the same stuff to others that had been previously done to them in their interviews.
Is it cheating or gaming the system if the vast majority of QUALIFIED engineers would not pass an interview without preparation? Reviewing these cheat sheets every couple of years is essentially part of the job.
Nice graphics! I really like from-the-bits-up explanations of things like this.
I found the newsletter upsell in the sidebar very distracting. I know you're considered a fool if you fail to bash people over the head with newsletter sign-up requests these days, but maybe just keep the ones interspersed in the text and get rid of the one I have to see all the time? Or I guess AB test it or whatever the cool kids are doing for this stuff. I dunno, but it really detracted from what I otherwise thought was great content.
It is a good site. I actually bought the product a year ago. But then I had to do something else which made me to not focus on getting an internship/job, and only recently I noticed it has a one year timeline. I think a one year time limit is too little for a 100 dollar product.
Honest feedback (short version): Very nice presentation, but for me the content loses credibility thanks partly to some silly mistakes but also to glossing over a few too many details.
Some examples:
The integer overflow part has incorrect binary/decimal conversions all over the place.
The example hash function used (summing elements modulo number of buckets) could be dangerous. I'm not generally a fan of showing bad practice or incorrect examples when teaching, even at an early stage when the student isn't ready for the real deal yet, but if you must then you could warn the reader that it's a simplistic example for demonstration and shouldn't be used in reality. It would not make a good impression if a candidate said they knew about hash tables but then produced that function as an example of hashing.
Similar comments apply to the treatment of big O notation. I understand that your style is to try to avoid being scary and complicated, but big O is useful because it has a specific meaning. Even in the longer explanation, you hardly mention that fundamentally it is about scalability and bounds, and you mention the danger of overlooking the constant factor only briefly right at the end. Also, the casual initial characterisation as being relative to the size of the input sets up traps when dealing with more sophisticated data structures, such as graphs where you often need to refer to the number of nodes and/or edges when specifying complexities.
Cool site. C++ graphics programmer here. I would like to add that knowing one thing extremely well - even a fairly small thing - can have amazing results in interviews. I can write just about anything, on command, in GLSL.
This has gotten me more interview offers and job offers than I can count, and it really didn't take me all that long to learn.
I hate to promote memorization, but honestly, it works. Some people argue that memorization isn't the same as learning, and it's not. But it definitely helps you learn and increases understanding.
Nice site but your questions are pretty run of the mill these days. Would be nice to see some new, original questions :-). Also an option to schedule some mock interviews would be great!
I got this recommendation about a year ago and tried. The site stated that I couldn't register, but I could sign up for a place in the registration queue.
So I did that. I have yet to hear back from them. I don't quite understand how people keep recommending them, as if it was possible to use the site.
Hey, I'm the founder of interviewing.io. We're coming out of private beta soon, which means we'll be sending out invites to folks on the waiting list shortly. A year is a long time though, and I'm sorry you had to wait that long, so I figured least I could do was kick you an invite (check your email). Thanks for being patient with us while we figured things out.
I guess it's a nice gesture, but this does nothing to address my point that, as far as I can tell, recommending interviewing.io to anyone is wildly inappropriate, and I can't see how it happens at all. (Not that you're the proper person to address that; it's more of a question for gameguy43 et al.) Are the people giving interviewing advice not actually even attempting to do the things they're recommending?
IIRC, folks who've recommended us on HN have used it (we get notified when people post about us bc it's obviously something we care about a lot). Sorry again about the delay, and I hope you like the product.
In the past, interviewing.io was free for anybody to try (it was when I looked at it three years ago) and if somebody hasn't looked at it recently they might not know when the situation has changed.
Sorry; I meant 'free' as in there wasn't a waiting list but checking my email I see that I was on the waiting list at first, too. I guess I'll just testify that people have used it. :)
Your explanations were excellent. I especially liked the way you introduced hash tables using a simple array where the indices had special meaning.
The diagrams are clear and helpful.
Only nitpick: not sure how somebody who is supposed to learn what an array is by reading this is supposed to already know the meaning of Big O notation. So maybe a little intro to Big O complexity somewhere in there would help as well.
Eep! Did you notice that the first time we mention big O notation, you can click on it and an inline explanation slides down? Probably not, based on the question! We should make that part louder.
The problem with links is that you don't know where they are going to take you. When I have such a nice piece of text to read I don't want to click and potentially land in a completely different site, have to click "back" and all that distracting stuff. That's probably why your link didn't "register" with me. In your case in turns out the link nicely expands in place, so that's pretty cool. I'd still just inline that little explanation on Big O, since you keep referring to it in the rest of the text. It's more than a mere footnote.
Now this is all my own experience, and others may disagree, so don't necessarily go changing things just on my account!
And eager to receive any feedback.
Thanks for the post!