Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Data Structures for Coding Interviews

interviewcake.com

Post reply on HN
Print view View original

131–140 of 238 posts

Re: Data Structures for Coding Interviews

#131

Post by sidlls »

seanwilson wrote: post #115
pavlov wrote: post #62

Hiring engineers based on data structure trivia is like hiring a marketing department based on spelling bee scores.

You'd really be fine hiring a senior developer that had no idea how a linked list, a hash table or a binary tree worked? Understanding which data structures are good for speed and memory usage is at a minimum required for memory constrained apps and dealing with large scale data.

Yes,I'd be fine with it as long as they could read and understand a table of data specifying the time and space complexity of various data structures and algorithms.

The amount of programming done in memory constrained apps and for large scale data is tiny in comparison to all programming, most of which is very basic CRUD type work meant for use in resource rich environments at small scale.

Re: Data Structures for Coding Interviews

#132

Post by fspear »

neerkumar wrote: post #28
gameguy43 wrote: post #5

Earlier quoted context omitted.

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.

Agree I would have signed up if it wasn't for the pricing...as it stands now it's totally not worth it.

Re: Data Structures for Coding Interviews

#133

Post by Terr_ »

thaumasiotes wrote: post #82
savanaly wrote: post #74

Earlier quoted context omitted.

In that one wouldn't want to hire someone as a marketer who couldn't spell "cat"? Not because it's necessary to be able to spell "cat", even, but because the inability to do so might indicate in a bayesian sense that the person is not likely equipped to do the job.

Not really apt as to spelling bees. High-level spelling bees try to use words that are as obscure as possible, because people will happily go forever on words they know. SAT vocabulary questions are chosen to be informative about the test taker's IQ; spelling bee words are chosen to be unfamiliar to everyone. You get a list of words that you're supposed to memorize; they could just as easily be random strings.

Exactly, it's analogous to how companies seek obscure interview question variants, sometimes explicitly stating that their goal is to to see "how you think" rather than to get the right solution.

Re: Data Structures for Coding Interviews

#134

Post by [deleted] »

thaumasiotes wrote: post #82
savanaly wrote: post #74

Earlier quoted context omitted.

In that one wouldn't want to hire someone as a marketer who couldn't spell "cat"? Not because it's necessary to be able to spell "cat", even, but because the inability to do so might indicate in a bayesian sense that the person is not likely equipped to do the job.

Not really apt as to spelling bees. High-level spelling bees try to use words that are as obscure as possible, because people will happily go forever on words they know. SAT vocabulary questions are chosen to be informative about the test taker's IQ; spelling bee words are chosen to be unfamiliar to everyone. You get a list of words that you're supposed to memorize; they could just as easily be random strings.

[deleted]

Re: Data Structures for Coding Interviews

#135

Post by sidlls »

nickrio wrote: post #97
bsamuels wrote: post #63

Earlier quoted context omitted.

i have the same feelings about "cracking the coding interview" the day someone unironically asks me to "Write an algorithm to print all ways of arranging eight queens on a chess board so that none of them share the same row, column or diagonal" - I will jump off a bridge

You can finish that algorithm and then ask for a *2 wage LOL

Or you can refuse to do that and then work on getting a position where you aren't treated like a monkey expected to do tricks on demand and also have a better wage and social status.

Re: Data Structures for Coding Interviews

#136

Post by philh »

fulafel wrote: post #122
ldite wrote: post #108

Earlier quoted context omitted.

1111 1111 = 255 1 0000 0000 = 256 Anyone who claims to understand integer overflow from actual experience, rather than memorizing textbooks, should know that by inspection. I'd forgive that in a CS grad (possibly) but if someone claimed to have been working in C or other unsafe languages for more than a trivial amount of time I'd be very suspicious.

That's only assuming 0-based numbers :)

(I know you're being tongue-in-cheek, but)

> our computer might compute the correct answer but then just throw out the 9th bit, giving us zero (0000 0000) instead of 257 (1 0000 0000)!

Re: Data Structures for Coding Interviews

#137

Post by Terr_ »

dcw303 wrote: post #32

This is a good cheat sheet for those who don't have (or have forgotten) the knowledge but want to game an algorithm heavy interview. The problem I got with this is exactly the same as when I tried reading the "Cracking the Coding Interview" book: I got through a few chapters and then the author mentions something off the cuff with an assumption that the reader will know what they mean. But of course, I don't, because…

You might like "The algorithm design manual" by Skiena. (Second edition.)

It's one of the few dead-tree books I ended up buying this year, albeit after perusing a library copy.

Re: Data Structures for Coding Interviews

#138

Post by PeterisP »

rootlocus wrote: post #109
bsamuels wrote: post #63

Earlier quoted context omitted.

i have the same feelings about "cracking the coding interview" the day someone unironically asks me to "Write an algorithm to print all ways of arranging eight queens on a chess board so that none of them share the same row, column or diagonal" - I will jump off a bridge

I went to a CS high-school (not university) and we studied backtracking in the first or second year. Everyone was supposed to know how to solve this and similar problems for tests.

Sure, you'd know that right after a CS high-school - however, if after that school you go on to work on real problems for a decade or two, then you won't know that anymore, since outside of very specific domains you don't really write such things from scratch anymore; you'd always want to use existing, optimized&tested implementations of all the common and less common data structures and traversal algorithms instead of rewriting them.

You forget what you don't use, and this is stuff that you don't use.

IMHO the big problem is that they're missing the point on why we ask students do do these algorithm implementations - it's not so that they'd learn how to do that (though a bit of general programming practice is useful), we put them there as hands on exercises so that students would understand the usage of these algorithms better.

The implementations are just a learning aid, not a learning goal. Asking to reimplement a red-black tree is somewhat comparable to asking what was shown in a particular instructional video or what practice problems were assigned in that class - checking if you remember the details of a particular teaching instrument.

Re: Data Structures for Coding Interviews

#139

Post by sidlls »

gaius wrote: post #129
bkovacev wrote: post #90

Earlier quoted context omitted.

> Array of problems a startup may face. Not every company is a startup. I'd much rather say a company like Google might have problems that require deep knowledge both inside and outside of someone's domain, but startups - no. They need to ship and optimize on the go, rinse and repeat. > With strong math and CS knowledge, you can reason through almost any problem. Until you can't. Math and CS, while certainly giving n…

Not every company is a startup. Exactly this. A company making microscopes probably doesn't need to hire biology PhDs, and wouldn't ask obscure biotrivia in an interview...

That's a good one. My friends in engineering (physical sciences based, e.g. aerospace) and I have decided that the analog in that industry to programming interviews would for the candidate to be bombarded with questions asking him to evaluate complicated integrals from the CRC or something like it.

Re: Data Structures for Coding Interviews

#140

Post by rdtsc »

pertymcpert wrote: post #110
rdtsc wrote: post #37

Earlier quoted context omitted.

I interviewed at some of these companies that liked the puzzles and so on. Then got to a company that actually seemed interested in stuff I've done before and asked enough details to know that I knew the stuff. I learned about what they did and seemed interested and got the job. Puzzles and tricks are like that are a crutch, because people don't know how to talk and find out about what the other person knows. Usually…

> I would usually think they became successful in spite of it. What...

That...
Post reply on HN