kostya_by's blog

Invitation to the August Lunchtime 2014 on CodeChef
By kostya_by, 10 years ago, In English

CodeChef invites you to participate in the August Lunchtime 2014 at http://www.codechef.com/LTIME15. This is an IOI style contest. This means that the problems will be partially graded. You will get score for passing certain test data.

Time: 31st August 2014, 1100 hrs to 1400 hrs. (Indian Standard Time — +5:30 GMT) — Check your timezone.

Details: http://www.codechef.com/LTIME15/

Registration: Just need to have a CodeChef user id to participate. New users please register here

- Problem Setter: Constantin Sokol
- Problem Tester: Gedi Zheng
- Editorialist: Lalit Kundu
- Russian Translator: Sergey Kulik
- Mandarin Translator: Gedi Zheng & Minako Kojima

It promises to deliver on an interesting set of algorithmic problems with something for all.
The contest is open for all and those, who are interested, are requested to have a CodeChef User ID, in order to participate.

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10 years ago, # |
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How to solve the 3rd problem? I have no idea about it.

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    10 years ago, # ^ |
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    Hi! The idea is to use bitmasks while doing BFS. Please, check out the editorial of this problem for more details.

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      10 years ago, # ^ |
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      Is it just me or have there been problems involving bitmask-optimization in the last 2 Cook-offs and this Lunchtime? :D

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        10 years ago, # ^ |
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        Well, I came up with the idea of doing BFS with bitmasks three months ago, so it seems to be a coincidence. =)

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      10 years ago, # ^ |
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      Oh, I see. I thought we can use the intersection of (edges from x) and (edges to unknow-distance nodes) to speed up.

      But can you proof your solution can indeed run in some complexity for all data?

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        10 years ago, # ^ |
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        My solution runs in O(Q * N ** 2 / 32 + sum M) time.

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10 years ago, # |
  Vote: I like it +6 Vote: I do not like it

The best lunchtime i have participated in till now. Thanks!

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