Ahmed_Morsy's blog

2D square root decomposition

By Ahmed_Morsy, history, 11 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

  • Vote: I like it
  • +5
  • Vote: I do not like it

»
11 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Auto comment: topic has been updated by Ahmed_Morsy (previous revision, new revision, compare).

→ Reply
»
11 years ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

, actually. And this complexity is reached with a quadtree.

→ Reply
  • »
    »
    11 years ago, hide # ^ |
    ← Rev. 2  
    Vote: I like it 0 Vote: I do not like it

    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

    → Reply
    • »
      »
      »
      11 years ago, hide # ^ |
       
      Vote: I like it +3 Vote: I do not like it

      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

      → Reply
»
11 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

You can try this problem http://www.codechef.com/SEPT14/problems/QRECT.

→ Reply