AyuAnchor's blog

NITS Hacks 6.0 Inter College Coding Competition (Prizes worth 50k INR)
By AyuAnchor, 6 months ago, In English

Calling all coders!

Get ready for the thrilling Competitive Programming Contest of NITS HACKS 6.0 in association with Coding Club NIT Silchar, under the event Tecnoesis, of NIT Silchar. The thrill and fun of team contest is back, with exciting prizes!

The coding competition is open to all undergraduate programmers in India, although everyone is encouraged to participate in it. It will be split into preliminary and final rounds according to ICPC guidelines (both rounds will be online). The final round awaits the top 30 preliminary teams out of which 10 spots are reserved for NIT Silchar Teams (excluding the top 20).

Rules:

  • A team of 2-3 members from the same college is required to participate in the contest.

  • An eligible individual may join only one team.

  • Each participant must have a Codeforces account.

  • A team must be created in Codeforces composed of the members.

  • Finally, you should register for the contest using the formed team.

  • The team must also register through the link provided below, not adhering to this requirement will make the team ineligible for winning prizes.

Registration Link:

Link: https://nitshacks.tecnoesis.co.in/event/3

Contest Time:

  • The Preliminary round will be on 1st February 2024 at 21:00 IST of duration 2:30 hrs.

  • The Final round will be held on 3rd February 2024 at 16:00 IST of duration 3 hrs.

Contest Link:

Click on the link below to take part in the contest. Registration for the contest will start 6 hours before the contest.

Link: https://codeforces.com/contestInvitation/629b54783ea94dadb04e65dbb6dcaa6d9897dd0d

Many thanks to all the people who made this round possible:

See You on the leaderboard!

UPD1: Registration has started.

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

Finally NITS HACKS is back after so long...Excited!!

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6 months ago, # |
  Vote: I like it +10 Vote: I do not like it

Excited!! 🤩

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

Excited for the contest!!!

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6 months ago, # |
  Vote: I like it +10 Vote: I do not like it

Thrilled for my first NITS HACKS !!!

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

Excited for the contest!!

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

Excited!!!

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

Excited!

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

Excited!!

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6 months ago, # |
  Vote: I like it +10 Vote: I do not like it

Do you have older NITS Hacks problemsets?

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

What's the deadline to fill the g-form?

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

    You can register anytime before the prelims.

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

Excited!!!!

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

Is single participation allowed?

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    6 months ago, # ^ |
      Vote: I like it +7 Vote: I do not like it

    Yes, you may participate as a one-person team. However it won't be considered as an official participation.

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6 months ago, # |
← Rev. 2   Vote: I like it +5 Vote: I do not like it

Excited for my first NITS hacks coding contest

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6 months ago, # |
← Rev. 2   Vote: I like it +4 Vote: I do not like it

Are participants from other country (other than India) eligible for prizes?

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

    As per rules, only Undergrads in India are eligible for the prizes.

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

have any previous question for practice?????

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

Back after sooo long.... EXCITED!!!!

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6 months ago, # |
← Rev. 2   Vote: I like it +16 Vote: I do not like it

If I rank within the top 20 on the general list, does this automatically make me one of the top 10 NITS teams, or are the top 10 from NITS determined separately? In other words, will there be more than 10 teams from NITS advancing to the next round, or is the top 10 from NITS a distinct category?

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    6 months ago, # ^ |
      Vote: I like it +15 Vote: I do not like it

    You are a good question.....!!!

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

    Great question! Ranking within the top 20 on the general list is definitely an impressive feat and puts you in a strong position in the competition. The determination of the top 10 NITS teams is indeed separate from the general top 20 teams.

    It's important to note that while the top 10 from NITS are highlighted separately, there can be obviously more than 10 teams from NITS advancing to the next round.

    All the best Anupam, see you in the ranking list

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

woohh......Excited

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

NIT Silchar orz

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6 months ago, # |
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Are dual degree students eligible for prizes?

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6 months ago, # |
  Vote: I like it +2 Vote: I do not like it

Excited!!!

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

Is individual eligible?

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

    You can participate, however you won't be considered an official participant.

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

I think you should extend the team to at least 40-50 for a Rigorous competition.

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6 months ago, # |
  Vote: I like it +7 Vote: I do not like it

According to current leaderboard till which rank the non-NIT Silchar teams get a chance for finals?

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6 months ago, # |
  Vote: I like it +15 Vote: I do not like it

Test Cases were well prepared.

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    6 months ago, # ^ |
      Vote: I like it +21 Vote: I do not like it
    Spoiler
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      6 months ago, # ^ |
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      Hi, I agree that most of the problems testcases were pretty nice and also fell for that case in spoiler. Problems were fun and some were a bit troll in good way.

      But before ending of contest, I was a bit frustrated with my code for $$$B$$$, and eventually I submitted my code with $$$O(K * K)$$$ loop in my $$$DFS$$$. So overall I think the Time Complexity of my code is $$$O(N * K * K + N * log(N))$$$ which should have not passed.

      Submission

      EDIT:

      Test Case
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      6 months ago, # ^ |
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      Test cases are weak for $$$H$$$.

      Hacked so many submissions :LOL:
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6 months ago, # |
← Rev. 2   Vote: I like it 0 Vote: I do not like it

[submission:244485212] can someone provide a counter example to this submission , for problem A. Its giving wrong answer for x=26 , in Testcase 2 , for every thing else its giving the correct answer , any reason/mathematical proof?

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

I have a confusion in question "B. Dora The Explorer", question guarantees that the given graph is a directed tree meaning every vertex should be reachable by the root (right?). But that is not true with some of the test cases. Many teams got wrong answer because of that. Is that test case correct? (test case 49)

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    6 months ago, # ^ |
    ← Rev. 2   Vote: I like it +1 Vote: I do not like it

    They considered that, if an edge directed upwards(towards root) then the subtree below that edge as unreachable.

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    6 months ago, # ^ |
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    i got so much penalty because of this , otherwise my team is in top 20

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

    By the definition provided in the link, we gave in the statement of question "B. Dora The Explorer" which we believed is accurate (source: Wikipedia). Our problem is totally based upon that definition of directed tree.

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

      Yes you are right, thank you for clarification.

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

Problem $$$C2$$$ could be made a little harder that may focuses on Suffix Automation by saying a substring wouldn't have more than maybe $$$X$$$ occurrences in total so that the whole problem could be solved in $$$O(N * logA + Q * X)$$$ where we could keep $$$X = sqrt(N)$$$ for betterment.

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    6 months ago, # ^ |
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    I do it with hashing so it didn't affect my code then also ig

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      6 months ago, # ^ |
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      you might have iterated over whole string? for each query it would be $$$O(N)$$$

      Via suffix automation (suffix array) we can iterate over only occurences so that will take $$$O(X)$$$ per query where $$$X$$$ is the maximum occurrence

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        6 months ago, # ^ |
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        Yaa got it I don't know much about suffix array, I solved less problem on it ~2 3 problem I look how it work for finding this thing Thanks for the idea

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    6 months ago, # ^ |
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    Ohh means you say like q.n constraint can be reduced right

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6 months ago, # |
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The round was Awesome! Will the editorials be released? Also can someone explain A please?

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

    if you do it directly , you get wrong since 10^x is always not divisible by 3. You should minus the remainder then you get the correct answer

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      6 months ago, # ^ |
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      Got it. Thank you!

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      6 months ago, # ^ |
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      Does this mean for (a/b)%M, when b divides a, then we can write it as (a%M / b)%M and then use MMI?

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        6 months ago, # ^ |
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        yaaa that is true or we write like  ((a%m)*((b)^-1)%m)%m

but here we need need 100/3  ~ not a integer , when you apply the above ,the decimal value also include which makes the answer wrong , to avoid that

a = a - (a%3)   , then you apply  , because you need floor value
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          6 months ago, # ^ |
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          Understood. Thanks for the explanation

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          5 months ago, # ^ |
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          can you share some articles or blog for it so i can learn in more better way . Videos or tutorials I have watched or read till now on MMI didn't use this technique that u used even when a%b!=0 i.e 100%3!=0 here.

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            5 months ago, # ^ |
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            This is not a technique , actually question wants the floor value , so i need to remove the remainder IN other cases no need to do that actually

            You can check the cp algorithm for MMI

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              5 months ago, # ^ |
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              okay got it but how did you realise that you have to remove the remainder?

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                5 months ago, # ^ |
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                in c++ , a/b is by default floor
         ex:  6 / 4 = 1  , not 1.5
         
 floor(a/b) = ((a -(a%b)) / b)

 4/4 = 5/4 = 6/4 = 7/4 = 1   (each one is floored 
                               so all are equal)  

The thing in dealing with modulo directly with floor, is that it modulod 1.5 not 1
This is case needed in question, that we need to apply modulo to the floor value not the whole
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6 months ago, # |
  Vote: I like it +7 Vote: I do not like it

where is editorial????

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

how i solve G "https://codeforces.com/gym/496831/problem/G" ?

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