hmehta's blog

By hmehta, history, 6 months ago, In English

Hi Everyone,

TCO20 Algorithm Finals – the most awaited Topcoder tournament of the year is almost here. Will tourist reign supreme or does someone else in the group have what it takes?

16 top-rated members will be competing in the next few weeks for the ultimate title of Topcoder Open. 

Here’s how the semifinal rounds look: 

Semi-Final 1 Group

Semi-Final 2 Group

Live Broadcast

TCO20 Algorithm Rounds will be broadcasted live and you’ll be able to listen to the amazing hosts Errichto and Lewin during the contest as they will explain the problems, do live commentary, and show you the competitors’ screens. They will be joined by some amazing guest competitors on each broadcast and also there are some exciting post match interviews planned too.

Find the full schedule with all the details and signup links to the event here

TCO20 Special Rookie SRM with Prizes

If you are new to Topcoder, we are also organising an interesting educational beginner contest with prizes after Semifinal 2:

TCO20 Special Rookie SRM

Wednesday, November 18, 2020 13:00 UTC-5

The Rookie SRM is open to everyone and has some special cash prizes. It will only be **rated** for members who have competed in equal to or less than 5 rounds or if their current rating is less than 800 rating points.

Prizes:

  • 1st :: $300
  • 2nd :: $200
  • 3rd :: $100
  • $25 for 5 other random participants
  • Topcoder T-shirt for Top 30
  • *All prizes are only for members who are eligible to be rated.

Stats — Algorithm Finalists Head to Head

We hope to see you there!

 
 
 
 
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6 months ago, # |
  Vote: I like it +18 Vote: I do not like it

Is it necessary for spectators to register somewhere? Why not just make a Youtube broadcast?

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6 months ago, # |
  Vote: I like it -41 Vote: I do not like it

Finally , a real match that isn't fix like MI vs DC where we can gamble and deserving will win . Not the person with more money (Ambani).

Btw, please post YouTube link also

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6 months ago, # |
  Vote: I like it -53 Vote: I do not like it

if their current rating is less than 800 rating points.
Can you please make it 1845 instead?
Thanks and Regards,
Aryan Choudhary

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6 months ago, # |
  Vote: I like it +23 Vote: I do not like it

hmehta, can we have official final standings together with decisions regarding challenges, finals quota and everything somewhere?

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6 months ago, # |
  Vote: I like it +6 Vote: I do not like it

I fixed some redundancy issues in my 500, and now I pass systests in 640 ms and 160 MB. But on my challenge case, my code takes over 20 seconds and several GB.

I'm very curious now what the reference solution is. Is it possible that my challenge requests timed out because my test case timed out the reference solution?

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    6 months ago, # ^ |
      Vote: I like it +76 Vote: I do not like it

    Lewin confirmed that my test case breaks the reference solution. That explains why my challenges on Jacob kept getting "Your request timed out."

    Here's the test case:

    1, 28, 41, 1, 6, 41, 38, 6, 4, 38, 48, 4, 14, 48, 52, 14, 12, 52, 31, 12, 22, 31, 27, 22, 11, 27, 39, 11, 23, 39, 35, 23, 9, 35, 30, 9, 7, 30, 47, 7, 20, 47, 44, 20, 3, 44, 40, 3, 8, 40, 33, 8, 24, 33, 49, 24, 16, 49, 32, 16, 10, 32, 34, 10, 5, 34, 37, 5, 17, 37, 51, 17, 13, 51, 36, 13, 15, 36, 46, 15, 21, 46, 43, 21, 2, 43, 29, 2, 19, 29, 45, 19, 26, 45, 42, 26, 18, 25, 42, 50, 25, 50, 28, 18
    

    The main idea is that the numbers 1-26 are all independent and set up at an odd distance, but they each affect the numbers 27-52 differently. The test case is a shuffled and slightly modified version of the following test case:

    1, 27, 28, 1, 2, 28, 29, 2, 3, 29, 30, 3, 4, 30, 31, 4, 5, 31, 32, 5, 6, 32, 33, 6, 7, 33, 34, 7, 8, 34, 35, 8, 9, 35, 36, 9, 10, 36, 37, 10, 11, 37, 38, 11, 12, 38, 39, 12, 13, 39, 40, 13, 14, 40, 41, 14, 15, 41, 42, 15, 16, 42, 43, 16, 17, 43, 44, 17, 18, 44, 45, 18, 19, 45, 46, 19, 20, 46, 47, 20, 21, 47, 48, 21, 22, 48, 49, 22, 23, 49, 50, 23, 24, 50, 51, 24, 25, 51, 52, 25, 26, 52, 27, 26
    

    This way, after the first 26 choices there are exactly $$$2^{26}$$$ different states. The number of states peaks at about $$$10^8$$$, for the prefix of length 28.

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      6 months ago, # ^ |
        Vote: I like it +20 Vote: I do not like it

      If TopCoder really managed to have problems with a model solution on finals two years in a row, I am quite impressed.

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      6 months ago, # ^ |
      Rev. 2   Vote: I like it +31 Vote: I do not like it

      I quite enjoyed that vibe "we have solved medium pretty much immediately, what are they doing, why are they going for hard" on stream. Yeah, we just decided that 2^26 * 26 is a bit too much and setter wouldn't go out of his way to set limitations to 52 if he wanted such solutions to pass.

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6 months ago, # |
Rev. 2   Vote: I like it +49 Vote: I do not like it
1000
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    6 months ago, # ^ |
      Vote: I like it +3 Vote: I do not like it

    Nice problem! I was close, I thought for some reason that edges not in MST in smaller parts should also be smaller than $$$k$$$, so I had to try $$$O(n^4)$$$ values for transition (to get wrong answer), but everything else is pretty much the same.

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6 months ago, # |
Rev. 2   Vote: I like it -10 Vote: I do not like it

Gentle Reminder: Registration for the Rookie SRM is now open :)

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5 months ago, # |
  Vote: I like it +23 Vote: I do not like it

Finals will start in 25 minutes! Watch on Hopin or Twitch (https://www.twitch.tv/topcoder_official).

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5 months ago, # |
  Vote: I like it +3 Vote: I do not like it

tourist aura?

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5 months ago, # |
  Vote: I like it +3 Vote: I do not like it

Feeling sad for um_nik with um_nik and 69 others.