Mitpro's blog

My first Div. 4 contest!
By Mitpro, 4 months ago, In English

Hello Codeforces

I am glad to invite you to take part in my contest. The round will be in ICPC style, but penalty won't count (if your solution is skipped, don't worry, I skip WA submissions to not count penalty). Note that problem K is supposed to be the last problem, but I am too lazy to change :). You can expect the difficulty of these problems to be Div. 4.

You will be given 13 problems to solve. It will start at Friday, January 9, 2026 at 22:15 (UCT+7) and ends at Friday, January 16, 2026 at 22:15 (UCT+7).

All the problems are authored my Mitpro

I would like to thank:

I hope you will enjoy the round and the problems!

This contest has already been made, but I decided to do make it become contest.

UPD1: Why do most of you register and do not solve the problems :(. I really want many people to solve it because I put a lot of time in the problems.

UPD2: Who ever gets top 10 after the contest ends will get a shout out, who ever gets top 5 will have the option to be co-author next round!

UPD3: Who ever gets top 15 after the contest ends will get have the option to be tester next round!

UPD4: Congratulations to the winners!

  1. MisterGir

  2. am_aadvik

  3. WA_ON_TEST_2

  4. rpam

  5. bramar2

  6. DigiTalDreamar

  7. wtf.rjdp1

  8. Zeeshan-Haider-Alvi

  9. kamyak

  10. Kalevion

UPD5: Editorial!

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

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

Good contest. The tasks are soo cool.

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4 months ago, hide # |
 
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Congrats, Div. 4 for CM :)

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

Good contest. Excellent problems. But I still don't understand why they added K, M — Maximum Flow and Manaker +DSU to the problems. I would classify K, M as div 3.

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    4 months ago, hide # ^ |
    ← Rev. 2  
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    My solution for M is greedy, you don't even need DSU! But yes, K is mainly data structure, which is not what I want, because you have to learn the algorithm, and I don't want the problem to be a knowledge wall

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    4 months ago, hide # ^ |
     
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    K is the most standard matching problem so it's not suitable for CF...

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4 months ago, hide # |
 
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problem H : There are n − 1 pipes

also problem H : wants to go to pipe n

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4 months ago, hide # |
 
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Great contest I enjoyed it

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4 months ago, hide # |
 
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K,J,M were nice F was just pure implementation (why)

Good contest overall

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4 months ago, hide # |
 
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In F shouldn't it be $$$0 \le |m_i| \le 10^5$$$ instead of $$$1 \le |m_i| \le 10^5$$$

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    4 months ago, hide # ^ |
     
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    Oh, yes, sorry, my bad. I will fix it right now.

    Next time, if you want to ask a question, ask in the contest page

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4 months ago, hide # |
 
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Very Good Contest :)

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

  1. MisterGir

  2. am_aadvik

  3. WA_ON_TEST_2

  4. rpam

  5. bramar2

  6. DigiTalDreamar

  7. wtf.rjdp1

  8. Zeeshan-Haider-Alvi

  9. kamyak

  10. Kalevion

  11. sqrteipi

  12. ShapeBlaze

  13. potatoArmy

  14. pandaa73

  15. TEAM LGM: MShaheer and Faraz

Who ever wants to become tester, DM me on my CF account, send me your discord account, I will send you the group invitation to my discord group for testers!

PLEASE DM ME YOUR DISCORD NAME SO I CAN ADD FRIEND YOU

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