hmehta's blog

By hmehta, history, 4 days ago, In English,

Hey All!

Topcoder SRM 760 is scheduled to start at 21:00 UTC -4, June 12, 2019. Registration is now open for the SRM in the Web Arena or Applet and will close 5 minutes before the match begins.

The round is prepared by teja349 and tested by Errichto

This is the third SRM of Stage 4 of TCO19 Algorithm.

Stage 4 TCO19 Points Leaderboard | Topcoder Java Applet | Next SRM 761 — June 22, 11:00 UTC-4

Good luck to everyone!

 
 
 
 
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4 days ago, # |
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There's a typo in the title, perhaps you meant SRM 760?

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4 days ago, # |
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Auto comment: topic has been updated by hmehta (previous revision, new revision, compare).

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3 days ago, # |
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Starts in 5 mins !

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3 days ago, # |
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Recently I got some time to start doing Topcoder, but I am really surprised to see that there are just about 250 participants in a single round. I heard that there was a time when Topcoder was very popular. Also the problems are nice and require insights. Does anyone know why it becomes not so popular all over time?

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3 days ago, # |
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    3 days ago, # ^ |
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    It's a bit like posting a link to a tutorial on flows when a problem requires a flow.

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3 days ago, # |
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How to solve 250 Div 1 ? I've tried but there were a lot of cases and I could not control all of them.

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    3 days ago, # ^ |
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    The first round has $$$C(N,N/2)$$$ ways to choose which teams play home and then $$$(N/2)!$$$ ways to match teams with each other. In the second round, home-away teams swap and you need to rearrange away teams so that nobody would play the same match. You need permutations that don't have an element $$$p_i = i$$$. This is called dearrangements and there's a recursive formula for that.

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      3 days ago, # ^ |
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      Thank you a lot ! :D

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      3 days ago, # ^ |
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      Darn, I didn't pay attention to the "nobody would play the same match".

      Beautiful problem, very elegant and "could actually happen" in the real world — maybe not with n=500000. :-)