hmehta's blog

Topcoder SRM 781
By hmehta, history, 4 years ago, In English

Hey All!

Topcoder SRM 781 is scheduled to start at 21:00 UTC -4, Mar 19, 2020. Registration is now open in the Web Arena or Applet and will close 5 minutes before the match begins.

Thanks to sinus_070 and misof for writing the problem set and coordinating the round. Also thanks to a.poorakhavan for testing and writing the editorials.

This is the eight SRM of Stage 2 of TCO20 Algorithm Tournament and TCO20 Regional Events Qualification

Stage 2 TCO20 Points Leaderboard | Topcoder Java Applet | Upcoming SRMs and MMs

Some Important Links
Match Results (To access match results, rating changes, challenges, failure test cases)
Problem Archive (Top access previous problems with their categories and success rates)
Problem Writing (To access everything related to problem writing at Topcoder)
Algorithm Rankings (To access Algorithm Rankings)
Editorials (To access recent Editorials)

Good luck to everyone!

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  • Vote: I do not like it

Comments Comments (13)
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4 years ago, # |
  Vote: I like it +8 Vote: I do not like it

Gentle Reminder: The match begins in 3 hours :)

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4 years ago, # |
  Vote: I like it 0 Vote: I do not like it

Reminder: Contest starts ~10 mins.
Good luck and I hope you enjoy the problems.

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4 years ago, # |
← Rev. 2   Vote: I like it 0 Vote: I do not like it

problem is not opening from last 20 minutes . it showing an empty page .screenshot

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4 years ago, # |
  Vote: I like it 0 Vote: I do not like it

What is the intended solution for div-1 450?

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    4 years ago, # ^ |
    ← Rev. 2   Vote: I like it +18 Vote: I do not like it

    The answer is always constant no matter how you partition it.

    Lets look at $$$sum(abs(A_i-B_i))$$$.

    If you colour the $$$n$$$ largest buildings in $$$H[]$$$ $$$blue$$$, and $$$n$$$ smallest $$$red$$$.
    In $$$sum(abs(A_i-B_i))$$$, exactly one of $$$A_i$$$ or $$$B_i$$$ is red and blue each. (Due to the condition that $$$A$$$ is non decreasing and $$$B$$$ is non increasing).
    For every $$$i$$$, $$$abs(A_i - B_i)$$$ will always be equal to $$$blue - red$$$.
    $$$sum(abs(A_i-B_i))$$$ = sum of heights of $$$blue$$$ buildings — sum of heights of $$$red$$$ buildings. Which is independent of how we're partitioning.

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4 years ago, # |
  Vote: I like it +26 Vote: I do not like it

The problems were very nice. I wish topcoder had more rounds like this one.

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4 years ago, # |
  Vote: I like it +32 Vote: I do not like it

Updated leaderboard: https://colab.research.google.com/drive/11UM7lZQ7-CCJiLAwVH1ENGfoyEEC28qs#scrollTo=1uhW3UC57lA8

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4 years ago, # |
  Vote: I like it +4 Vote: I do not like it

Editorial link?

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4 years ago, # |
  Vote: I like it +3 Vote: I do not like it

Hey hmehta,

The rating on the main profile page is running 3 SRMs behind:

https://www.topcoder.com/members/royappa/

The latest is shown here:

https://www.topcoder.com/members/royappa/details/?track=DATA_SCIENCE&subTrack=SRM

Just FYI. Thanks!

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