AyuAnchor's blog

By AyuAnchor, 4 weeks 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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4 weeks 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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4 weeks ago, # |
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Excited!! 🤩

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4 weeks ago, # |
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Excited for the contest!!!

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4 weeks ago, # |
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Thrilled for my first NITS HACKS !!!

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4 weeks ago, # |
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Excited for the contest!!

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4 weeks ago, # |
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Excited!!!

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4 weeks ago, # |
  Vote: I like it +8 Vote: I do not like it

Excited!

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

Excited!!

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4 weeks ago, # |
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Do you have older NITS Hacks problemsets?

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4 weeks 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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    4 weeks ago, # ^ |
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    You can register anytime before the prelims.

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4 weeks ago, # |
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Excited!!!!

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4 weeks ago, # |
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Is single participation allowed?

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    4 weeks ago, # ^ |
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    Yes, you may participate as a one-person team. However it won't be considered as an official participation.

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4 weeks 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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4 weeks ago, # |
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Are participants from other country (other than India) eligible for prizes?

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    4 weeks ago, # ^ |
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    As per rules, only Undergrads in India are eligible for the prizes.

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4 weeks ago, # |
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have any previous question for practice?????

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4 weeks ago, # |
  Vote: I like it +8 Vote: I do not like it

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

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4 weeks ago, # |
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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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    4 weeks ago, # ^ |
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    You are a good question.....!!!

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    4 weeks ago, # ^ |
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    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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3 weeks ago, # |
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woohh......Excited

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3 weeks ago, # |
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NIT Silchar orz

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3 weeks ago, # |
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Are dual degree students eligible for prizes?

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3 weeks ago, # |
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Excited!!!

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3 weeks ago, # |
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Is individual eligible?

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    3 weeks ago, # ^ |
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    You can participate, however you won't be considered an official participant.

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3 weeks ago, # |
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I think you should extend the team to at least 40-50 for a Rigorous competition.

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3 weeks ago, # |
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According to current leaderboard till which rank the non-NIT Silchar teams get a chance for finals?

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3 weeks ago, # |
  Vote: I like it +15 Vote: I do not like it

Test Cases were well prepared.

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    3 weeks ago, # ^ |
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    Spoiler
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      3 weeks 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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      3 weeks ago, # ^ |
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      Test cases are weak for $$$H$$$.

      Hacked so many submissions :LOL:
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3 weeks ago, # |
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[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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3 weeks ago, # |
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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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    3 weeks ago, # ^ |
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    They considered that, if an edge directed upwards(towards root) then the subtree below that edge as unreachable.

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

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    3 weeks ago, # ^ |
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    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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      3 weeks ago, # ^ |
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      Yes you are right, thank you for clarification.

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

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      3 weeks 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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        3 weeks 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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    3 weeks ago, # ^ |
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    Ohh means you say like q.n constraint can be reduced right

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

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    3 weeks ago, # ^ |
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    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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      3 weeks ago, # ^ |
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      Got it. Thank you!

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      3 weeks 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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        3 weeks 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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          3 weeks ago, # ^ |
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          Understood. Thanks for the explanation

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          2 weeks 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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            2 weeks 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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              2 weeks ago, # ^ |
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              okay got it but how did you realise that you have to remove the remainder?

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                13 days 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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3 weeks ago, # |
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where is editorial????

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3 weeks ago, # |
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how i solve G "https://codeforces.com/gym/496831/problem/G" ?