ninjamayank's blog

AlgoUtsav 2024 Inter College Coding Competition (Prizes worth 50K INR)
By ninjamayank, history, 8 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.me/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!!

  • Vote: I like it
  • +12
  • Vote: I do not like it

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

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

→ Reply
»
8 months ago, # |
  Vote: I like it 0 Vote: I do not like it

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

→ Reply
»
8 months ago, # |
  Vote: I like it +3 Vote: I do not like it

Prize breakdown?

→ Reply
»
8 months ago, # |
  Vote: I like it 0 Vote: I do not like it

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

→ Reply
»
8 months ago, # |
  Vote: I like it +2 Vote: I do not like it

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?

→ Reply
»
8 months ago, # |
  Vote: I like it +5 Vote: I do not like it

When will the editorial be provided

→ Reply
»
8 months ago, # |
  Vote: I like it +2 Vote: I do not like it

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.

→ Reply
  • »
    »
    8 months ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    Same problem.

    → Reply
    • »
      »
      »
      8 months ago, # ^ |
      ← Rev. 2   Vote: I like it 0 Vote: I do not like it

      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

      → Reply
      • »
        »
        »
        »
        8 months ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        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)

        → Reply
        • »
          »
          »
          »
          »
          8 months ago, # ^ |
            Vote: I like it 0 Vote: I do not like it 
          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?
          → Reply
    • »
      »
      »
      8 months ago, # ^ |
        Vote: I like it +3 Vote: I do not like it

      Thanks!

      → Reply
    • »
      »
      »
      8 months ago, # ^ |
        Vote: I like it +3 Vote: I do not like it

      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.

      → Reply
      • »
        »
        »
        »
        8 months ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        Where is the editorial

        → Reply
        • »
          »
          »
          »
          »
          8 months ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

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

          → Reply
  • »
    »
    8 months ago, # ^ |
      Vote: I like it +3 Vote: I do not like it

    Xor basis Technique

    → Reply
  • »
    »
    8 months ago, # ^ |
    ← Rev. 2   Vote: I like it 0 Vote: I do not like it

    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.

    → Reply
    • »
      »
      »
      8 months ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      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

      → Reply
»
8 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Can anyone tell how to approach problem h.

→ Reply
»
8 months ago, # |
  Vote: I like it 0 Vote: I do not like it

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

→ Reply