### hmehta's blog

By hmehta, history, 16 months ago,

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

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!

• +14

 » 16 months ago, # |   +8 Gentle Reminder: The match begins in 3 hours :)
•  » » 16 months ago, # ^ |   +6 Timing of the contest is way too ODD.
 » 16 months ago, # |   0 Reminder: Contest starts ~10 mins.Good luck and I hope you enjoy the problems.
 » 16 months ago, # |   0 Great timing for the Indian community :)
 » 16 months ago, # | ← Rev. 2 →   0 problem is not opening from last 20 minutes . it showing an empty page .screenshot
 » 16 months ago, # |   0 What is the intended solution for div-1 450?
•  » » 16 months ago, # ^ | ← Rev. 2 →   +18 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.
 » 16 months ago, # |   +26 The problems were very nice. I wish topcoder had more rounds like this one.
•  » » 16 months ago, # ^ |   +14 Thank you!It is encouraging to hear that, as this is my first attempt at problem setting.
•  » » » 16 months ago, # ^ |   0 Indeed!
 » 16 months ago, # |   0 Auto comment: topic has been updated by hmehta (previous revision, new revision, compare).
 » 16 months ago, # |   0 Auto comment: topic has been updated by hmehta (previous revision, new revision, compare).
 » 16 months ago, # |   +32
 » 16 months ago, # |   +4 Editorial link?
•  » » 16 months ago, # ^ |   +3 Here it is editorial
 » 16 months ago, # |   +3 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=SRMJust FYI. Thanks!
•  » » 15 months ago, # ^ |   0 This is now fixed :)
•  » » » 15 months ago, # ^ |   0 Thanks!Of course when I reported it I had just got to Div1. Now it will highlight my immediate drop to Div2!! :-))