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

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

Idea: ToxicPie9

Preparation: flamestorm

**Hint**

**Solution**

**Video Editorial**

**Feedback**

Idea: BucketPotato

Preparation: BucketPotato

**Hint**

**Solution**

**Feedback**

Idea: ToxicPie9

Preparation: ToxicPie9

**Hint 1**

**Hint 2**

**Solution**

**Feedback**

Idea: AlperenT

Preparation: AlperenT

**Hint 1**

**Hint 2**

**Hint 3**

**Solution**

**Feedback**

1812E - Not a Geometry Problem

Idea: ToxicPie9

Preparation: ToxicPie9

**Hint**

**Solution**

**Feedback**

Idea: flamestorm

Preparation: flamestorm

**Hint**

**Solution**

**Feedback**

Idea: flamestorm

Preparation: flamestorm

**Hint 1**

**Hint 2**

**Solution**

**Feedback**

Idea: ToxicPie9

Preparation: ToxicPie9

**Hint 1**

**Hint 2**

**Solution**

**Feedback**

**Hint**

**Solution**

**Feedback**

Idea: ScarletS, ToxicPie9, et al.

Preparation: ToxicPie9, ~~ChatGPT~~

**Hint**

**Even Bigger Hint**

**Solution**

**Feedback**

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

Another guessforces round? Come on codeforces

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

Or factordb

There is another way to solve problem

FSpoiler200166327

the best contest i have ever done!

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

I was 168th on contest to first time WOW

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.

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

Will it be rated?

problems are tarsh el tarsh

Is your profile picture yourself?

No,all people here doesn't put their photos like you

it's something good why downvote

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

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

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

Getting the same thing:

Download the image to see the color. The color seems a little different on website.

The colour on the downloaded image still seems to be #007327:(

I imported the downloaded image into GIMP, then I got #01722B.

Well, maybe there's something wrong with my image.

Yes, you are right and I did as you said. Finally, I got the correct output.

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

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.

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

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.' :(

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

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

This contest is so funny :)) And I have solved 5 problem !!

When I first did this contest I was really unbelieved about my life :(((

I am not sure why 20,21 are unrated. This blog clearly states both contests are rated.

It's asking about the first 25 rounds ever, not the most recent 25.

Sorry. I fast read the solution and skipped the word 'first'

**Thanks **

best contest!!!!!

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.