ninjamayank's blog

AlgoUtsav 2024 Inter College Coding Competition (Prizes worth 50K INR)
By ninjamayank, history, 9 months ago, In English

Are you ready to take your programming skills to new heights?

The Algorithmic and Programming Society (APS) of NIT Rourkela proudly presents AlgoUtsav 2024! This coding competition is open to all undergraduate programmers across India. Whether you're a seasoned coder or just starting out, AlgoUtsav offers an opportunity to challenge yourself and showcase your talent.

The contest will be held online according to ICPC guidelines

Rules and Guidelines:

  • AlgoUtsav 2024 is open to all Indian college students, providing a platform for young minds to showcase their coding skills.
  • Teams must consist of 2-3 members, and all team members must belong to the same organization encouraging collaboration and teamwork.
  • Multiple registrations will not be allowed to ensure fairness and equal opportunity for all.
  • Sharing solutions during the contest period is strictly against the rules, promoting integrity and individual effort.
  • Any attempt to deliberately destabilize the testing process or hack the contest will result in immediate disqualification, upholding the integrity of the competition.

Registration Link:

Link: https://unstop.com/p/algoutsav-2024-nit-rourkela-905708

Contest Timing:

The contest will be on 16th February 2024 at 14:30 IST of duration 3:00 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.net/contestInvitation/94c98ba6995d24eb14165d5801d0805da1a0eddc

Special thanks to MikeMirzayanov for amazing Codeforces and Polygon platforms.

See you on the leaderboard!!

UPD1: The Registrations have started!

UPD2: Editorial is out!!

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9 months ago, # |
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Auto comment: topic has been updated by ninjamayank (previous revision, new revision, compare).

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9 months ago, # |
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9 months ago, # |
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Prize breakdown?

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9 months ago, # |
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9 months ago, # |
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I have no other CP person in my school, so I can't meet atleast 2 people from same organization requirement. Please can something be done for it?

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9 months ago, # |
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When will the editorial be provided

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9 months ago, # |
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Could Someone please give the idea or approach of problem C ? I tried thinking in direction of DP but got nowhere as range was too large to make submask as DP state. I tried some random constructive ideas but they didn't worked either. help appreciated.

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    9 months ago, # ^ |
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    Same problem.

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      9 months ago, # ^ |
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      Bro did you solve the B problem I think of gausss elimination but don't know how to correct implement it

      i tried the code from cp algorithm , but it is for n = m , n+1 th column for B (Ax = B)

      But i don't know what to do , i make matrix then max(n , m) * max(n ,m) Please help!

      Thanks

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        9 months ago, # ^ |
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        I was getting WA. Not sure what I missed. But, here are my insights:

        You can get stuck at infinite solutions if you go with max(n, m) * max(n, m) matrix.

        Instead, what's better is: find the variables (columns) which are non-zero in >= 1 row. That will be the n for you. Now, take n rows from the given m rows (if m < n, definite answer is not possible): and here you get the n x n base matrix with an additional (n + 1)th column in each row being the number of days (for that row)

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          9 months ago, # ^ |
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          i seen the submission of the people have solved it

they use the same code for n,m 
Means it will work for n,m  also right

Now i know like , in Ax = B
         B has entries like D[i] + k1*365
So we need to do something like crt right to find the first value, then corresponding k1 k2 .. can be found

But what they doing like , 5 * 73 = 365 , 5 as p1 , 73 as p2



Did you know what they do?
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      9 months ago, # ^ |
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      Thanks!

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      9 months ago, # ^ |
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      I read the editorial but I am unable to follow the row canonical optimization part and if possible could you also give some resource for the proof of why and how is it working.

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        9 months ago, # ^ |
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        Where is the editorial

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          9 months ago, # ^ |
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          Oh! Sorry for not being clear. I read the editorial of the problem mentioned by 18o3 in the comment, not the contest's editorial.

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    9 months ago, # ^ |
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    Xor basis Technique

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    9 months ago, # ^ |
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    Let the xor of all elements in the array be $$$x$$$. The bits where $$$x$$$ has $$$1$$$, will be set in one subset xor and unset in the other regardless of the choice of subsets. For bits which are unset in $$$x$$$, we can have either them set in both subsets or unset in both. To maximise, just consider all unset bits in $$$x$$$ and find the maximum xor subset over the array.

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      9 months ago, # ^ |
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      My doubt lies in your last line, that how do we find maximum xor subset over the array. I saw the atcoder editorial and it was using some canonical row transformation which I was unable to understand that why was it working

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9 months ago, # |
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Can anyone tell how to approach problem h.

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9 months ago, # |
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