7 ms·

No offence to Twitter, but this is a seriously bad way of hiring developers. What are you trying to recruit mathematics scholars as developers? When will compan

No offence to Twitter, but this is a seriously bad way of hiring developers. What are you trying to recruit mathematics scholars as developers? When will companies like Twitter learn not all great developers are math geniuses? I didn't even get a college education to get where I am, I failed maths in school as well, but I can code, so what does that mean? I think it means nothing in the greater scheme of things. By the sounds of it the author got a better position in the end, I'd rather be working at Amazon who are solving much better problems than Twitter ever will likely solve anyway. If a company (no matter how great they were) tried asking me these kinds of questions, I would immediately stop the interview and thank them for the opportunity.

raverbashing 13y ago
Well, you may want to hire math scholars. I think it's important to have some in your team. But it's also important to focus on other aspects as well.
bloometal 13y ago
I have no idea why a bunch of people here keep saying these questions are good for recruiting 'mathematics scholars'. Fact: I am a mathematics graduate student and I would not be able to solve this problem. I hope there isn't a notion that people studying mathematics spend all their time solving Project Euler type questions. In fact I would be thrilled if they are recruiting for math people. They are not. I have been in the job market for a while now and recruiters literally stop listening when they don't hear "CS" in the first sentence.
codenut 13y ago
What made you say that twitter is trying to recruit math genius? The author's solution involves calculus while the intended solution is only a loop and some if statements. I actually like interview problems like that. It requires critical thinking which shows how the candidates think and it is also almost impossible to google.
onion2k 13y ago
"this is a seriously bad way of hiring developers" We can't reasonably assume that Twitter uses this sort of question in all their developer interviews. We don't have enough data for that. Perhaps this guy was going for a role where solving problems quickly and under pressure was a key requirement. If that were the case, this is pretty much a perfect interview question.
- smsm42 13y ago
  I have hard time imagining what position, at least if we're talking about software engineering, would require solving abstract toy problems in a timeframe of less than an hour without a chance to ever go back and improve your solution. I'd say it's "did you see this problem before" kind of question. Which means Twitter probably lost a capable and smart hire because he couldn't quickly give a perfect answer to useless puzzle (unless of course he was hired to repair the roof in Twitter's office and solving this puzzle is required for Twitter to survive the rainy season). Hardly a "perfect" way.
  - etler 13y ago
    Twitter interview puzzle creator?
    - smsm42 13y ago
      You can take months to create puzzles, there's no pressure here.
- stefan_kendall 13y ago
  The problem is that this is a bread and butter ACM problem. Anyone who has competed will know the solution. And biasing for ACM competitors is awful.
virtuz 13y ago
The intended solution is basic math – addition and subtraction. I don't have a PHD, degree in CS, nor have I studied advanced math but I can still figure it out. It's all about how you look at problems. If you can analyse problems, break them down and create simple, novel solutions without much effort—that's not with an overnight sleep, as sometimes you'll need to craft solutions immediately—you're a good candidate. That's exactly the sort of thing these questions test.

raverbashing 13y ago

Well, you may want to hire math scholars. I think it's important to have some in your team. But it's also important to focus on other aspects as well.

bloometal 13y ago

I have no idea why a bunch of people here keep saying these questions are good for recruiting 'mathematics scholars'. Fact: I am a mathematics graduate student and I would not be able to solve this problem. I hope there isn't a notion that people studying mathematics spend all their time solving Project Euler type questions. In fact I would be thrilled if they are recruiting for math people. They are not. I have been in the job market for a while now and recruiters literally stop listening when they don't hear "CS" in the first sentence.

codenut 13y ago

What made you say that twitter is trying to recruit math genius? The author's solution involves calculus while the intended solution is only a loop and some if statements. I actually like interview problems like that. It requires critical thinking which shows how the candidates think and it is also almost impossible to google.

onion2k 13y ago

"this is a seriously bad way of hiring developers" We can't reasonably assume that Twitter uses this sort of question in all their developer interviews. We don't have enough data for that. Perhaps this guy was going for a role where solving problems quickly and under pressure was a key requirement. If that were the case, this is pretty much a perfect interview question.

smsm42 13y ago
I have hard time imagining what position, at least if we're talking about software engineering, would require solving abstract toy problems in a timeframe of less than an hour without a chance to ever go back and improve your solution. I'd say it's "did you see this problem before" kind of question. Which means Twitter probably lost a capable and smart hire because he couldn't quickly give a perfect answer to useless puzzle (unless of course he was hired to repair the roof in Twitter's office and solving this puzzle is required for Twitter to survive the rainy season). Hardly a "perfect" way.
- etler 13y ago
  Twitter interview puzzle creator?
  - smsm42 13y ago
    You can take months to create puzzles, there's no pressure here.
stefan_kendall 13y ago
The problem is that this is a bread and butter ACM problem. Anyone who has competed will know the solution. And biasing for ACM competitors is awful.

virtuz 13y ago

The intended solution is basic math – addition and subtraction. I don't have a PHD, degree in CS, nor have I studied advanced math but I can still figure it out. It's all about how you look at problems. If you can analyse problems, break them down and create simple, novel solutions without much effort—that's not with an overnight sleep, as sometimes you'll need to craft solutions immediately—you're a good candidate. That's exactly the sort of thing these questions test.