Ahmed_Morsy's blog

2D square root decomposition

By Ahmed_Morsy, history, 9 years ago, In English

I was wondering if there is a problem solvable on a 2D grid using square root decomposition :-) or if anyone used it before

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9 years ago, # |
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Auto comment: topic has been updated by Ahmed_Morsy (previous revision, new revision, compare).

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9 years ago, # |
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, actually. And this complexity is reached with a quadtree.

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    9 years ago, # ^ |
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    Yeah but I was wandering if it could be useful, a friend of mine went to ioi 2013, he met a medalist who solved game using square root decomposition on 2D grid :-) unfortunately, he doesn't know details

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      9 years ago, # ^ |
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      It's really similar to basic sqrt decomposition, (we build small squares 1x1, large squares sqrt x sqrt and stripes 1x sqrt and ofc sqrt x 1) Game was solveable with that, but I don't think that for 100 points.. Here's one task from Polish OI, enjoy it :) http://main.edu.pl/en/archive/oi/13/tet

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9 years ago, # |
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You can try this problem http://www.codechef.com/SEPT14/problems/QRECT.

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