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Don't write on the whiteboard

jperla.com

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Re: Don't write on the whiteboard

#111

Post by pjscott »

jodrellblank wrote: post #91
ljlolel wrote: post #76

Earlier quoted context omitted.

That works if each phrase is one word. Many (most?) of the terms in the vocabulary are multi-word phrases. How would your algorithm work for multiple word phrases? What is its running time?

It would have to be altered; let's see: Create hashtable where the key is the first word and the value is (rest of sentence, link). In the case of collisions, a list of rest of sentences and links. Checking the document would still go word by word, if no lookup fine, if one result compare the rest of phrase with the following document words, if a list, do that repeatedly. Runtime varies a lot with distribution of inp…

In the case of collisions, you need to search for a bunch of possible rest-of-sentence phrases in the text. This is exactly the problem that your algorithm tries to solve! If you apply it recursively, you get, essentially, trie matching with words instead of characters.

http://en.wikipedia.org/wiki/Trie

Re: Don't write on the whiteboard

#112

Post by jodrellblank »

pjscott wrote: post #111
jodrellblank wrote: post #91

Earlier quoted context omitted.

It would have to be altered; let's see: Create hashtable where the key is the first word and the value is (rest of sentence, link). In the case of collisions, a list of rest of sentences and links. Checking the document would still go word by word, if no lookup fine, if one result compare the rest of phrase with the following document words, if a list, do that repeatedly. Runtime varies a lot with distribution of inp…

In the case of collisions, you need to search for a bunch of possible rest-of-sentence phrases in the text. This is exactly the problem that your algorithm tries to solve! If you apply it recursively, you get, essentially, trie matching with words instead of characters. http://en.wikipedia.org/wiki/Trie

There is some bunch searching, but most of the document doesn't get searched, and the bits which get searched aren't searched for most of the keyphrases.

Instead of:

    For phrase in keyphrases:
        If phrase in document:
            pass
This

    For word in document:
        Some_phrases = get_keyphrases_starting[word]
        if document.next_5_words.find(some_phrases)
Instead of searching 100,000 keyphrases in the whole document, this searches 10 rest-of-sentences in the 5 words following a mention of 'phospholipid', 18 rest-of-sentences in the 3 word following 'proteomerase' and nothing in the text about the lab temperature, and never touches most of the keyphrases at all for the document.

Re: Don't write on the whiteboard

#113

Post by suneilp »

bethling wrote: post #88
ljlolel wrote: post #78

Earlier quoted context omitted.

Parents of children and teachers don't seem to have a problem with paper.

I don't have a problem with paper - I just feel like it would work against a candidate - not because "Oh...they used paper", but because some of the things that I think are signs of a good candidate don't show through. I've never interviewed a candidate that asked me to use paper, so I can't be sure - it's just my instinct. It might be completely biased though - I far prefer to use whiteboards - I love the space, I l…

What do you do when your too tall for the whiteboard because some short stubby interviewer placed it lower than normal to accomodate his stubbiness.

Re: Don't write on the whiteboard

#114

Post by denzil_correa »

edw519 wrote: post #9

Sorry OP, I realize that you're just trying to be helpful sharing what's worked for you and I appreciate that, but frankly, I hate posts like this... I think the best preparation for any interview is to simply get good at what you do. All the rest is window dressing that distracts from that goal. Every minute spent practicing interviewing would be better spent building stuff. The natural byproduct of this will be exe…

I actually agree with Ed here. You should worry about things in your control rather than thinking about things beyond your control. I understand that interviews aren't fair etc. but I still believe keeping it simple is the best way to success.

Simplicity is the ultimate sophistication.-- Leonardo Da Vinci

Re: Don't write on the whiteboard

#115

Post by rimantas »

edw519 wrote: post #9

Sorry OP, I realize that you're just trying to be helpful sharing what's worked for you and I appreciate that, but frankly, I hate posts like this... I think the best preparation for any interview is to simply get good at what you do. All the rest is window dressing that distracts from that goal. Every minute spent practicing interviewing would be better spent building stuff. The natural byproduct of this will be exe…

  > I think the best preparation for any interview is to
  > simply get good at what you do
Isn't that exactly the problem? How often are you asked to do the stuff you do best in the interview? Coding algorithms on the whiteboard is not what I do best.

Re: Don't write on the whiteboard

#116

Post by Tooluka »

dkarl wrote: post #80

The interviewers don't care. Use paper. Uh, yeah, we do care. Part of what we're judging is your ability to present and explain your work. How you do your work is your business, but how you share it affects the people you work with. If you think it's all about you, then you're off on the wrong foot already.

We don't commit new code to whiteboards. We commit it to VCS. You know, with such electronic thingies, called computers. And when my interviewers wanted to collaborate they didn't find it too difficult with paper. Even sitting opposite of me (and that is why large tables in conferences are evil).

Re: Don't write on the whiteboard

#117

Post by grot »

jebblue wrote: post #79
bethling wrote: post #44

Earlier quoted context omitted.

As an interviewer, I'd much rather see your intermediate steps - the messy parts, etc. I feel like I can get a better idea about how you work and think. Interview questions (for me) aren't about "can you solve this" they're more about trying to see how you work. I ask questions about decisions you made, and I like it if you can talk about what you're thinking. Interview problems are contrived. I don't care if you stu…

That sounds more like a visit with Froyd than a programmer interview.

Freud?

Re: Don't write on the whiteboard

#118

Post by aoeuid »

The poster is right -- don't write on a whiteboard. Instead, bring your laptop, make the font bigger on your favorite editor, and write in that. I've gone through many interviews like this, and only one interviewer insisted I use the whiteboard. And I'm pretty sure that was largely out of wanting to be fair to other candidates who didn't think to bring and use their laptops.

Since you will presumably be writing code on a computer when working at the company, why not write code on a computer when interviewing with one?

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