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) |

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Algorithm Rankings | (To access Algorithm Rankings) |

Editorials | (To access recent Editorials) |

Good luck to everyone!

Gentle Reminder: The match begins in 3 hours :)

Timing of the contest is way too ODD.

Reminder: Contest starts ~10 mins.

Good luck and I hope you enjoy the problems.

Great timing for the Indian community :)

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

What is the intended solution for div-1 450?

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.

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

Thank you!

It is encouraging to hear that, as this is my first attempt at problem setting.

Indeed!

Auto comment: topic has been updated by hmehta (previous revision, new revision, compare).Auto comment: topic has been updated by hmehta (previous revision, new revision, compare).Updated leaderboard: https://colab.research.google.com/drive/11UM7lZQ7-CCJiLAwVH1ENGfoyEEC28qs#scrollTo=1uhW3UC57lA8

Editorial link?

Here it is editorial

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!

This is now fixed :)

Thanks!

Of course when I reported it I had just got to Div1. Now it will highlight my immediate drop to Div2!! :-))