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The first one is a knapsack problem: http://en.wikipedia.org/wiki/Knapsack_problem http://en.wikipedia.org/wiki/Knapsack_problem The third on is Zero-sum probl

The first one is a knapsack problem: http://en.wikipedia.org/wiki/Knapsack_problem http://en.wikipedia.org/wiki/Knapsack_problem The third on is Zero-sum problem: http://en.wikipedia.org/wiki/Zero-sum http://en.wikipedia.org/wiki/Zero-sum Nor sure about the second one. Anyone who knows?

duskwuff 16y ago
Second one isn't a traditional algorithms problem, as the "correct" result is subjective.
mayank 16y ago
The second problem seems open-ended and a test of UX/creativity skills: "There is no objectively 'right' answer here, and in fact there may be multiple ways to interpret a provided list of file events." The third problem is not zero-sum, it's subset-sum: http://en.wikipedia.org/wiki/Subset_sum http://en.wikipedia.org/wiki/Subset_sum I never understood the value of these simplified competitions. If your goal is to test implementations of approximation algorithms, then at least make the conditions realistic, like the Netflix prize.
- benmathes 16y ago
  These simplified competitions seem to filter for applicants who can recognize the canonical problems like knapsack/zero-sum/etc. and then successfully implement them.
- Andys 16y ago
  While you might think of these sorts of problems as simplified, they really do work well to filter out the sort of programmers you definitely don't want to hire. And for many programmers you might want, its a simple enough problem that it isn't very time-consuming for them.
- tel 16y ago
  I think the Netflix prize is a pretty bad comparison since it fueled years of active research from top machine learning and data mining people. It's great work, but if you're trying to find new hires the time scale is quite a ways off.
  - mayank 16y ago
    On the contrary, within a few days of the Netflix prize challenge being launched, a guy put up a detailed blog post with a simple linear algebra method that could beat Netflix's system at the time (link below). It didn't come anywhere near the 10% improvement threshold, but it beat Netflix's system with a handful of lines of C code, and it ran off his laptop. Sounds like he would have made an excellent hire. http://sifter.org/~simon/journal/20061211.html http://sifter.org/~simon/journal/20061211.html
    - tel 16y ago
      Haha, I stand very well corrected!
- GoogleMeElmo 16y ago
  >"The third problem is not zero-sum, it's subset-sum: http://en.wikipedia.org/wiki/Subset_sum http://en.wikipedia.org/wiki/Subset_sum That is correct. I have messed the names up :P
ilija139 16y ago
I think you are killing the point with this answers.
- dfox 16y ago
  Naming problem you are trying to solve does not always solve it. Even more so for problems where common belief is that only way to solve them is essentially brute-force and what counts are various tricks in the actual implementation of solution.
dfox 16y ago
First one is not knapsack problem (which is about packing largest possible value into available "capacity" without regard to actual geometry of considered objects), but one variant of packing problems.

duskwuff 16y ago

Second one isn't a traditional algorithms problem, as the "correct" result is subjective.

mayank 16y ago

The second problem seems open-ended and a test of UX/creativity skills: "There is no objectively 'right' answer here, and in fact there may be multiple ways to interpret a provided list of file events." The third problem is not zero-sum, it's subset-sum: http://en.wikipedia.org/wiki/Subset_sum http://en.wikipedia.org/wiki/Subset_sum I never understood the value of these simplified competitions. If your goal is to test implementations of approximation algorithms, then at least make the conditions realistic, like the Netflix prize.

benmathes 16y ago
These simplified competitions seem to filter for applicants who can recognize the canonical problems like knapsack/zero-sum/etc. and then successfully implement them.
Andys 16y ago
While you might think of these sorts of problems as simplified, they really do work well to filter out the sort of programmers you definitely don't want to hire. And for many programmers you might want, its a simple enough problem that it isn't very time-consuming for them.
tel 16y ago
I think the Netflix prize is a pretty bad comparison since it fueled years of active research from top machine learning and data mining people. It's great work, but if you're trying to find new hires the time scale is quite a ways off.
- mayank 16y ago
  On the contrary, within a few days of the Netflix prize challenge being launched, a guy put up a detailed blog post with a simple linear algebra method that could beat Netflix's system at the time (link below). It didn't come anywhere near the 10% improvement threshold, but it beat Netflix's system with a handful of lines of C code, and it ran off his laptop. Sounds like he would have made an excellent hire. http://sifter.org/~simon/journal/20061211.html http://sifter.org/~simon/journal/20061211.html
  - tel 16y ago
    Haha, I stand very well corrected!
GoogleMeElmo 16y ago
>"The third problem is not zero-sum, it's subset-sum: http://en.wikipedia.org/wiki/Subset_sum http://en.wikipedia.org/wiki/Subset_sum That is correct. I have messed the names up :P

ilija139 16y ago

I think you are killing the point with this answers.

dfox 16y ago
Naming problem you are trying to solve does not always solve it. Even more so for problems where common belief is that only way to solve them is essentially brute-force and what counts are various tricks in the actual implementation of solution.

dfox 16y ago

First one is not knapsack problem (which is about packing largest possible value into available "capacity" without regard to actual geometry of considered objects), but one variant of packing problems.