AlperenT's blog

Editorial of April Fools Day Contest 2023
By AlperenT, 20 months ago, In English

Thank you for participating in our contest! We hope you enjoyed it.

Please let us know what you thought of the problems by voting!

1812A - Are You a Robot?

Idea: ToxicPie9
Preparation: flamestorm

Hint
Solution
Video Editorial
Feedback

1812B - Was it Rated?

Idea: BucketPotato
Preparation: BucketPotato

Hint
Solution
Feedback

1812C - Digits

Idea: ToxicPie9
Preparation: ToxicPie9

Hint 1
Hint 2
Solution
Feedback

1812D - Trivial Conjecture

Idea: AlperenT
Preparation: AlperenT

Hint 1
Hint 2
Hint 3
Solution
Feedback

1812E - Not a Geometry Problem

Idea: ToxicPie9
Preparation: ToxicPie9

Hint
Solution
Feedback

1812F - Factorization

Idea: flamestorm
Preparation: flamestorm

Hint
Solution
Feedback

1812G - Colour Vision

Idea: flamestorm
Preparation: flamestorm

Hint 1
Hint 2
Solution
Feedback

1812H - Expected Twist

Idea: ToxicPie9
Preparation: ToxicPie9

Hint 1
Hint 2
Solution
Feedback

1812I - Mountain Climber

Idea: Ari
Preparation: Ari

Hint
Solution
Feedback

1812J - Unmysterious Language

Idea: ScarletS, ToxicPie9, et al.
Preparation: ToxicPie9, ChatGPT

Hint
Even Bigger Hint
Solution
Feedback
  • Vote: I like it
  • +163
  • Vote: I do not like it

Comments Comments (29)
| Write comment?
»
20 months ago, # |
  Vote: I like it +54 Vote: I do not like it

I knew what I was doing clicking on the "Video Editorial" link. Was not disappointed)

→ Reply
»
20 months ago, # |
  Vote: I like it -11 Vote: I do not like it

Another guessforces round? Come on codeforces

→ Reply
»
20 months ago, # |
  Vote: I like it +45 Vote: I do not like it

F: https://www.dcode.fr/prime-factors-decomposition did the trick :)

→ Reply
»
20 months ago, # |
  Vote: I like it +59 Vote: I do not like it

There is another way to solve problem F

Spoiler
→ Reply
»
20 months ago, # |
  Vote: I like it +7 Vote: I do not like it

the best contest i have ever done!

→ Reply
»
20 months ago, # |
  Vote: I like it +44 Vote: I do not like it

There were some who solved B in another way. 2015 is the only year that did not have an April Fools round, and 2020 and 2021's rounds had a problem "Is it rated?" and the answer was a clear NO. In other years it's just YES

→ Reply
»
20 months ago, # |
  Vote: I like it +1 Vote: I do not like it

I was 168th on contest to first time WOW

→ Reply
»
20 months ago, # |
← Rev. 2   Vote: I like it -7 Vote: I do not like it

https://math.stackexchange.com/questions/2900616/what-le-500-digit-number-has-62-118-steps-collatz-conjecture

http://www.ericr.nl/wondrous/index.html

If anyone is interested in the 142023 limitation of D, you can read this two. This is helpful. The above article provides a good generation method, and the following article guesses that the solution exists.

→ Reply
»
20 months ago, # |
  Vote: I like it -16 Vote: I do not like it

is it rated ? was it rated ? Guess the next....

→ Reply
»
20 months ago, # |
  Vote: I like it -39 Vote: I do not like it

problems are tarsh el tarsh

→ Reply
»
20 months ago, # |
  Vote: I like it +27 Vote: I do not like it

Using Ai as jury was amazing, Is it possible to see new problems based on that ?

→ Reply
»
20 months ago, # |
  Vote: I like it +16 Vote: I do not like it

Thanks to all authors for very good contest, every problem is genius, and my favourite one is $$$H$$$. By the way, does anyone know, is there any website or something for competitions like April Fools Day Contest? From year to year I like this contests more and more, will be cool to participate in something like that more often than 1 time in a year

→ Reply
»
20 months ago, # |
  Vote: I like it +7 Vote: I do not like it

In problem G, is the green really #01722B? I find it is #007327.

→ Reply
»
20 months ago, # |
  Vote: I like it +16 Vote: I do not like it

Anyone else who thought B meant the last 25 contests? Coincidentally, the 15th contest (counting from the most recent) actually was unrated...

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

    I think so too... actually the 25th contest (counting from the most recent) was also unrated and n<=25, so I thought it was the right approach.

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

I wish every other were also this easy!!! :D

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

My whole contest experience was terrible due to the internet problems. And for problem B when I went to check whether the 25 rounds rated, codeforces told me 'The page is temporarily blocked by administrator.' :(

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

    I thought it was made on purpose. I tried API, didn't work as well. I had to use Wayback Machine...

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

      All right, I had never heard of it, but I have now. Thx~

      → Reply
»
20 months ago, # |
  Vote: I like it +1 Vote: I do not like it

best contest!!!!!

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

I solved Problem D — Trivial Conjecture by finding the number. Submission: 200174057

The one I used is: 274133054632352106267

I found it on an obscure site linked on a github page. I don't actually know how long the sequence is though, since the site only cites the biggest number reached. Here being 56649062372194325899121269007146717645316.

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

not the rickroll...lmao

→ Reply