Nickolas's blog

By Nickolas, 4 weeks ago, In English

The contest is over; I hope you enjoyed it! The editorial is available here.


The 9th April Fools Day Contest will take place on Thursday April 1st. This is a joke competition in which solving the problem is often easier than figuring out what the actual task is.

In this round you'll be given several weird problems and 2 hours to solve them. The contest will use ACM ICPC rules (no hacks, the standings are decided by the number of solved problems and penalty time earned on them), and it will be unrated. You can submit solutions in any language allowed by Codeforces, unless the problem says otherwise. To get an idea of what the contest will look like, you can check out the contests of the past years: 2012, 2013, 2014, 2016, 2017, 2018, 2019, 2020.

Good luck, and have fun!

 
 
 
 
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4 weeks ago, # |
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Is it rated?

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4 weeks ago, # |
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Today I learned that Arnold Schwarzeneggar has a whole language dedicated to him.

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3 weeks ago, # |
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'problem is often easier than figuring out what the actual task is' it means it will be fun without any cost/rewards. Hahaha... Interesting

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    3 weeks ago, # ^ |
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    sir it is only a song on youtube, where is the editorial??????

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    3 weeks ago, # ^ |
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    Wow, what an amazingly interesting and detailed editorial! Thanks!

    For problem D, how do you implement the part where it says

    We've known each other for so long

    Your heart's been aching, but you're too shy to say it

    Inside, we both know what's been going on

    We know the game, and we're gonna play it

    I'm having a bit of trouble with my code here, can anyone help?

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      2 weeks ago, # ^ |
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      We've known each other for so long

      • This is a reminder to use 64 bit integers to avoid overflow in intermediate calculations of cross products.

      Your heart's been aching, but you're too shy to say it

      • Since this is a cancerous 3D geometry problem, it causes terrible heartburn for anyone who attempts to spend the 5 hours required doing geometry implementation. The problemsetter is too shy to add the geometry tag to the problem though, because he is afraid of the downvotes on the editorial that will follow.

      Inside, we both know what's been going on

      • Only the points inside the 3D convex shell matter. Both Alice and Bob know to only pick these inner points.

      We know the game, and we're gonna play it

      • This one goes without saying: it's a competitive programming problem, so of course this just winds up being a game of, you guessed it, Nim.
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        2 weeks ago, # ^ |
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        Thanks for this detailed explanation.

        I couldn't solve this by myself. I guess I am just too blind to see this hidden meaning.

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    3 weeks ago, # ^ |
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    not funny, especially when everyone knows XcQ

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    2 weeks ago, # ^ |
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    Sorry but I have memorized the link lol

    maybe you should hide the link under the text

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      2 weeks ago, # ^ |
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      it still will be visible in the lower left corner

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    2 weeks ago, # ^ |
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    I'm still waiting for a year when the statement for one of the tasks in April Fools day contest is just this

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    2 weeks ago, # ^ |
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    большое спасибо за редакционную статью (thank you so much for the editorial)

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    2 weeks ago, # ^ |
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    Everyone know what's that I memorized the link :D Good effort tho

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3 weeks ago, # |
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Given I already know one of the problem, Should I become one of the tester? :P

April Fool's Problem

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3 weeks ago, # |
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1

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2 weeks ago, # |
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If you practice you will become red

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2 weeks ago, # |
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Unrated rounds are always exciting!! It will be fun to give this round :)

"_This is a joke competition in which solving the problem is often easier than figuring out what the actual task is._"That's funny xD

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good luck every body!!1! i hope to reach gren

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2 weeks ago, # |
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it would be fun if there were hacks in the contest

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    2 weeks ago, # ^ |
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    can you explain this..didnt get it.

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      2 weeks ago, # ^ |
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      Just observe what's written below A, B1, B2, and C.

      7045, 5658 and 3987 are common years while 1964 is a leap year.

      So basically that's the reason why the guy got sad.

      Wasn't that obvious ?

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Finally a rated contest XD

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Also known as: April Rage Contest :p

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Good luck to everyone! I hope this "competition" will be cool and funny.)

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.

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submit more than five times then get the ac.....

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is it a rated contest?

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2 weeks ago, # |
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what if at the start of the contest they say APRIL FOOL there is no contest.

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Believe nothing and trust no one. Today is April Fool’s Day!

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How to be a good coder?? Can you tell me some way to think the solution for a problem? I don't know where to start or what to think first!

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2 weeks ago, # |
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will this contest be helpful for placements

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    2 weeks ago, # ^ |
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    this is the placement -.-

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    2 weeks ago, # ^ |
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    All questions asked in Today's contest will be repeated in placement test.Hurry up!Remember All questions.If u missed even single testcase You will not going to get 1cr.

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The comment is hidden because of too negative feedback, click here to view it

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How Many Problems will be there and problem ratings?

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2 weeks ago, # |
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not conduct the contest and tell everyone that we fool u guys :)

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Spoiler
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2 weeks ago, # |
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Can we think that the fact this round will be unrated is also April's fools day's joke? :)

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2 weeks ago, # |
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2 weeks ago, # |
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would you even believe today if I tell you something real?? Brave browser which is an open source web browser is now acquired DuckDuckGo which is a search engine mainly focuses on privacy of user.

Let me know if you think I am making you fool.. because you may be fool if you think I am making you fool. LOL

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2 weeks ago, # |
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Wait is today April 1st? I thought today is March 32nd

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What if, it turns out, they were fooling us about the contest' start time and we all got fooled :v

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    2 weeks ago, # ^ |
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    What if, it turns out, they were fooling us about the contest being unrated and we all got fooled ¯_(ツ)_/¯

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hello!

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2 weeks ago, # |
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aprilfool.

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2 weeks ago, # |
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Kinda sad that this blog post be getting more upvotes than 3 educational round announcements combined

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Beginner tutorial on Map/Dictionary.

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I am Not able to see the question?

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How the hell is tourist first even in this contest XD. I can't even get past the 2nd problem. I even searched if there's a thing such as digital millennium calculation act in desperation.

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    2 weeks ago, # ^ |
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    In this type of contest, difficulty distribution is not always objective so you should read all problems. For example, I couldn't solve B either but could C and E.

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2 weeks ago, # |
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Am I April fooled by the server almost not working for me 30 minutes?

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IS IT RATED? IS IT RATED? IS IT RATED?

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lol ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎

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Why were the people's solution for I skipped? anathor April fool prank?

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    2 weeks ago, # ^ |
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    By the way who all recieved my personal message. I didnot mean it. I was joking!

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This contest made me realize that besides being dumb, I am also a brick.

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No worry, the Standings will be inverted!

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SecondThread solved B after 37 incorrect submissions.

Sounds like me solving a task after reading the editorial.

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    2 weeks ago, # ^ |
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    B example: input: 54817 ans: 7 5 + 4 + 8 + 1 + 7 = 25; 2 + 5 = 7; So the ans is 7 :)

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Me googling about roots (B-DMCA)

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The biggest problem to solve I was to wait for custom invocation to run something :(

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Can anyone explain D and/or F?

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Nice contest. Too bad the custom invocation for the secret language doesn't return anything most of the time. Was H a program for Z80 processor? I solved it just by looking at hexdump, not sure if that was intended.

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what is the secret language?

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    2 weeks ago, # ^ |
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    The Seriously programming language (later renamed to Actually; also, it seems that the version on the server is outdated, as several commands didn't work there).

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Seriously, how to get better at doing April Fools Day Contest?

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It is a rare experience to find that you get passed for a problem that the god did not...

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Could anyone tell me the idea of C?

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    2 weeks ago, # ^ |
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    s[i] — 'A' == (s[i — 1] — 'A' + s[i — 2] — 'A') % 26

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    HINT: sum of ASCII value of previous two characters

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    Check s[i] == (s[i — 1] + s[i — 2]) % 26 for every i >= 2. Don't forget to subtract 65 from every letter. (65 is 'A' in ASCII) Code

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    2 weeks ago, # ^ |
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    you have to take alphabets as number i.e. A=1,B=2,...

    As written Fibonacci suggests that the previous two char's addition should give the current char

    if string follows such pattern then YES else NO ( if length of string<=2 then print YES )

    if any two characters addition exceeds 26 i.e. U+V=20+21=41 then take modulo with 26 i.e. (U+V)%26=15

    My solution : 111691458

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    2 weeks ago, # ^ |
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    Thanks guys for your help.

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ToOoOoOo000 Hard!!!

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2 weeks ago, # |
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BrainFuck Contest

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    2 weeks ago, # ^ |
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    For F, I was googling "How to write brainfuck in brainfuck ? "

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      2 weeks ago, # ^ |
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      Lol, I actually tried submitting brainfuck in english, because it was giving some different answer on custom innovation with Secret Programming Language

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Can someone tell me how they decoded the braille in F? I spent an hour but couldn't find any good online converter.

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How to solve B?

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Could somebody explain the language?

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why answer in B is (x — 1) % 9 + 1?

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Fancy contest! But that feeling when i see editorial of problem D,

but you know how it is when you're trying to remember a fancy-sounding word and come up with all kinds of similar-looking ones?

Spoiler
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The worst fool I am in the whole world . Today I came to know? and By the way miss You , you fKing foolish day.

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Is april a fool day . Is 1st april a fool month. Is this day maker a fool. Was celebrater a fool. Or we are fools?

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Problem I : Unlike the past years, this time any code you submit in ``Secret 2021'' language will run successfully — or at least produce no recognizable error.

Meanwhile submiting fuck you gives RTE and tells you the name of the language.

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Is there anyone other than me who didn't like the problemset? :/

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Explanation for problem H and I here.

Prepared by my friend not me :D