Dominater069's blog

Invitation to Codechef Starters 115 (Rated for All) — 3rd January
By Dominater069, history, 11 months ago, In English

We invite you to participate in CodeChef’s Starters115, this Wednesday, 3rd January, rated for All.

Time: 8:00 PM — 10:30 PM IST

Joining us on the problem setting panel are:

Written editorials will be available for all on discuss.codechef.com. Pro users can find the editorials directly on the problem pages after the contest. The video editorials of the problems will be available only to Pro users.

Also, if you have some original and engaging problem ideas, and you’re interested in them being used in CodeChef's contests, you can share them here.

All problems except 2 are made by me. Hope you find them interesting, but constructive criticism is also appreciated. There will be a total of 11 problems, out of which 7 will be scoreable for division 1 and 8 scoreable problems for every other division.

Hope to see you participating. Good Luck!

UPD : The contest got extended by 30minutes to a total of 2.5hours.

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11 months ago, # |
  Vote: I like it +40 Vote: I do not like it

Dominater dominating cc round setting

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11 months ago, # |
  Vote: I like it +9 Vote: I do not like it

Hope this one is not guessforces and edgecaseforces like the previous one.

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    11 months ago, # ^ |
      Vote: I like it +47 Vote: I do not like it

    not that last round was bad or anything, but this round is definitely high quality

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11 months ago, # |
  Vote: I like it +61 Vote: I do not like it

Dominater069 shared with me some of his problems in this round and they are great... Recommend to participate!

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11 months ago, # |
  Vote: I like it +51 Vote: I do not like it

As a gray tester, some of the problems really scared me.

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11 months ago, # |
  Vote: I like it +38 Vote: I do not like it

MridulAhi orz tester

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11 months ago, # |
  Vote: I like it +11 Vote: I do not like it

This Contest is also termed as (Hello 2024) on Codechef.

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11 months ago, # |
  Vote: I like it +24 Vote: I do not like it

For many of us, this was a very exciting moment where we would potentially get to write a contest with beautiful and interesting problems.

For Dominater069, however, it was a Wednesday.

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11 months ago, # |
  Vote: I like it +13 Vote: I do not like it

Please try to add more sample test cases if possible. Like in last contests chef and tag problem i wasted a lot of time as i missed the point that we cannot tag in leaf Node which wouldn’t have happened if a simple sample like 1-0 would have been added
i know it’s my skill issues but still

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

Auto comment: topic has been updated by Dominater069 (previous revision, new revision, compare).

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11 months ago, # |
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I hope to become green in this round

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11 months ago, # |
  Vote: I like it 0 Vote: I do not like it

pupil making contest XD

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11 months ago, # |
← Rev. 2   Vote: I like it +7 Vote: I do not like it

Hoping the problem will be well-cooked with right amount of spiciness.

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11 months ago, # |
  Vote: I like it +45 Vote: I do not like it

Contest starting in little under an hour. Hope to see you participating and best of luck. Do read and try atleast the next couple of problems.

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11 months ago, # |
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is it only me who cannot view problems yet?

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11 months ago, # |
  Vote: I like it +5 Vote: I do not like it
Today's round in a picture

This apart, problems were pretty nice. Dominater069 orz.

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

Hello, I hope you liked the problemset, do leave your feedbacks.

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    11 months ago, # ^ |
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    fun problems i enjoyed the contest

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    11 months ago, # ^ |
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    problems were nicely explained and easy to understand.
    Thanks

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    11 months ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    It was really fun. "Subtraction Subsequence I" was just amazing! (wasn't able to solve II :( ).

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11 months ago, # |
← Rev. 2   Vote: I like it +20 Vote: I do not like it

Problems were really cool! Great job authors!

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11 months ago, # |
  Vote: I like it +14 Vote: I do not like it

SUBSEQ1 and SUBSEQ2 are great! thanks for the problemset!

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11 months ago, # |
  Vote: I like it +33 Vote: I do not like it

I liked COUNTISFUN10 and SUBSEQII, thanks! Perhaps even better if modulos in the a contest are the same.

By the way what should I do to keep hiding Live Ratings Graph after refreshing the page?

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

    Glad that you liked COUNTISFUN10

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    11 months ago, # ^ |
      Vote: I like it +25 Vote: I do not like it

    Thanks for the feedback! We'll try to make the Live Ratings Graph section minimization / maximization 'sticky' through refreshes.

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    11 months ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    i always try to keep 10^9 + 7, COUNTISFUN10 was already prepared with a different modulo by a different author, so i did not change it

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

why tls so tight? i cry ;-;

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    11 months ago, # ^ |
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    btw which TL was tight? i kept most TLs quite loose from intended solution, except for COUNTISFUN (only a 2.5x or so) but that didnt have TLE issues

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      11 months ago, # ^ |
        Vote: I like it -8 Vote: I do not like it

      Subseq1 ;-; Due to a deficit in my IQ I was using segtree with a complexity of nlognlogn which tls. Later when I did it without segtree it gets ac

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        11 months ago, # ^ |
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        can you please explain your soln. i also think of a soln using binary search with range min and rang sum query but then i realized binary search won't work.

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          11 months ago, # ^ |
          ← Rev. 4   Vote: I like it 0 Vote: I do not like it

          i think -i am also on the same way ,why binary search will not work with lazy seg assuming no tles??

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            11 months ago, # ^ |
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            fist let me explain why i'am using binary search. for a segment i .. n — 1 i'am finding j such that sum(i..j) > minele(j + 1..n — 1) but then i realize it's not monotonic.

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11 months ago, # |
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Is Binary Grid Forces DSU?

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

    It's just some implementation and finding a nCr.

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11 months ago, # |
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problemset was really cool..... after so long I enjoyed participating in codechef contest !

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11 months ago, # |
  Vote: I like it 0 Vote: I do not like it

In Problem Binary Grid Forces

Testcase

Which sequence of operations will form S1 as 10011.

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    11 months ago, # ^ |
      Vote: I like it +7 Vote: I do not like it
    1. Swap $$$S_{1,2}$$$ and $$$S_{1,3}$$$. $$$S_1 = 11001$$$.
    2. Swap $$$S_{2,3}$$$ and $$$S_{2,4}$$$. $$$S_2 = 11010$$$.
    3. Swap $$$S_{1,2}$$$ and $$$S_{1,4}$$$. $$$S_1 = 10011$$$.
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11 months ago, # |
  Vote: I like it -9 Vote: I do not like it

Please pay $$$5,000*\text{The no of users who converted from free tire to paid tier plus Russian GST}$$$ in rupees as using codeforces blog post for commercial use

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11 months ago, # |
  Vote: I like it +8 Vote: I do not like it

As a Div 4 participant, I really liked the problemset!

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