Deadwing's blog

By Deadwing, history, 3 months ago, In English,

In the last 2 rated Div1 rounds there were 2 problems with such good points that can be solved by just writing a brute force and figuring out a pattern and then you may kiss the bride.

815B - Karen and Test

809C - Find a car

How does it seem to you?

 
 
 
 
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3 months ago, # |
  Vote: I like it -22 Vote: I do not like it

By the way how many non-english natives here who know the meaning of "notorious" :'D

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    3 months ago, # ^ |
      Vote: I like it +145 Vote: I do not like it

    I came across the word in a comment I read (it was in English) way back.

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    3 months ago, # ^ |
    Rev. 2   Vote: I like it +10 Vote: I do not like it

    Although one wouldn't use "notorious" in such a context :3

    Edit: Sorry, didn't know about the notorious coincidence you are referring to XD

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3 months ago, # |
  Vote: I like it +36 Vote: I do not like it

I hope that in 809C - Find a car you aren't talking about thing that the value in cell (i, j) is (j - 1)xor(i - 1) + 1... If you are, then you should read about Sprague Grundy theorem. If you are talking about that recursion, then you should read about how xor behaves. I can bet that most of participans didn't write brute force to this problem, it's well known that this matrix behaves like this. If it comes to problem 815B - Karen and Test, then yes, it isn't the most interesting sort of problems, but imo it's not so bad on individual contests, where you have computer just for yourself and brute force is easy to implement and gives much.

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    3 months ago, # ^ |
      Vote: I like it -24 Vote: I do not like it

    Seems you got aggressive after getting up to top 10 :( (Yeah rating changes people)

    Anyway, it's a programming contest, I can bet that most of participants would write a brute and recognize the pattern for 5 minutes rather than thinking for > 10 minutes of an interesting solution and fapping after getting the idea. I bet most people fap after getting higher rating more frequently than after getting nice ideas (However I'd fap for nice ideas)

    Problems alike shouldn't exist in my opinion in a CF round (This comment will be downvoted because you are who you are and I am just a normie but I don't care), It make some get what they may not deserve.

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      3 months ago, # ^ |
        Vote: I like it +27 Vote: I do not like it

      Huh, hold on, your comment looks much more aggresive to me :P. As for me and find a car — I knew that it is i^j with some +-1 instant I saw that picture, I already encountered exactly same matrix at least 3 times and it is not hard to come up with it from scratch (smallest integer not present in some set — sounds pretty familiar, probably has some connection with games theory, xors etc). However I was not able to solve the problem even though I spent a long time on it. As for today's problem, yes, I agree it is kind of problem when you need to write a bruteforce to notice the pattern but I think such problems are completely fine, especially on individual contests.

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        3 months ago, # ^ |
          Vote: I like it -27 Vote: I do not like it

        I really hate that situation when you sit and boost your brain to come up with an idea. I tried some binomial shit today (but seems I am not experienced enough), anyway in the end couldn't come up with something. But when most of people wrote that it was patterns stuff I was pretty much like

        and BTW this post was just for fun and mentioning the notorious coincidence but seems your friend has been so much serious recently :D I hope he hasn't been friendzoned

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          3 months ago, # ^ |
            Vote: I like it +31 Vote: I do not like it

          I would say I am rather experienced with binomials and shit but I would say there was no way to concluding how does it look like without writing bruteforce. Problems like that happen from time to time, it is not something extraordinary.

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            3 months ago, # ^ |
              Vote: I like it +27 Vote: I do not like it

            You are stressed so much guys, I think that I should just post it here for you.

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              3 months ago, # ^ |
                Vote: I like it +399 Vote: I do not like it

              Yo mama waited 9 months for systests and she got WA

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                3 months ago, # ^ |
                  Vote: I like it +42 Vote: I do not like it

                ;_;

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                  3 months ago, # ^ |
                    Vote: I like it +88 Vote: I do not like it

                  Yo mama so fat she falls on both sides of the bed at the same time.

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                  3 months ago, # ^ |
                  Rev. 2   Vote: I like it +172 Vote: I do not like it

                  deadwing

                  You started a civil war in Poland :P

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                  3 months ago, # ^ |
                    Vote: I like it +317 Vote: I do not like it

                  When yo mama creates grid problems she gives first number of columns and then number of rows

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                  3 months ago, # ^ |
                    Vote: I like it +65 Vote: I do not like it

                  Yo mama so ugly her face is just one giant presentation error.

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                  3 months ago, # ^ |
                    Vote: I like it +181 Vote: I do not like it

                  When yo mama creates contests she uses dynamic scoring

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                  3 months ago, # ^ |
                    Vote: I like it +40 Vote: I do not like it

                  Yo mama so stupid on Distributed Code Jam she was solving A throughout entire contest.

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                  3 months ago, # ^ |
                    Vote: I like it +138 Vote: I do not like it

                  Yo mama records screencasts

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                  3 months ago, # ^ |
                    Vote: I like it +160 Vote: I do not like it

                  And yo mama watches them.

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                  3 months ago, # ^ |
                    Vote: I like it +95 Vote: I do not like it

                  Yo mama asks if it's rated

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                  3 months ago, # ^ |
                    Vote: I like it +193 Vote: I do not like it

                  Yo mama got compilation error on test 57.

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                  3 months ago, # ^ |
                  Rev. 3   Vote: I like it -127 Vote: I do not like it

                  yo mamas are funnier than chinese

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                  3 months ago, # ^ |
                    Vote: I like it +123 Vote: I do not like it

                  And yo mama got "Can't find file C:\Contesters\Work\invoker-prod\work\codeforces2\b00a58c7139058a693e243e272a449d7\check-aa5f5d80dec38086488721f39ffc5878\run\output.fd0138e687.txt"

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                  3 months ago, # ^ |
                    Vote: I like it +98 Vote: I do not like it

                  Yo mama still wonders who sorry_dreamoon is.

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                  3 months ago, # ^ |
                  Rev. 2   Vote: I like it +16 Vote: I do not like it

                  Yo mama failed a relatively easy problem on a first day

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                  3 months ago, # ^ |
                    Vote: I like it +69 Vote: I do not like it

                  Yo mama's graphs can contain loops and multiple edges.

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                  3 months ago, # ^ |
                    Vote: I like it +65 Vote: I do not like it

                  Sorry man, Swistakk won

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                  3 months ago, # ^ |
                    Vote: I like it +56 Vote: I do not like it

                  Yea, I guess people don't know what was problem A on DCJ about :/

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                  3 months ago, # ^ |
                    Vote: I like it -27 Vote: I do not like it

                  Your mamas read all the comments.

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                  3 months ago, # ^ |
                    Vote: I like it -8 Vote: I do not like it

                  yo mamas are are proud of you both :D

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                  3 months ago, # ^ |
                  Rev. 2   Vote: I like it +115 Vote: I do not like it

                  "When yo mama creates grid problems she gives first number of columns and then number of rows"

                  and square samples.

                  P.S. You guys should create a twitter with jokes.

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                  3 months ago, # ^ |
                    Vote: I like it -43 Vote: I do not like it

                  Seems there are so many chinese here such that my comment got -115. I guess all of them were like: Calm down it's just a joke.

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          3 months ago, # ^ |
            Vote: I like it +17 Vote: I do not like it

          I think brute-forcing is just another idea to try during contest, neither better, nor worse.

          However, my way to find the solution was to draw some pyramids for some short sequences like a b c, a b c d. When you notice a+c b+d in the third row of pyramid beginning with a b c d, you can smell something interesting, when you extend the first row with e f then magically a+2c+e b+2d+f in the fifth row appears, you can continue that process, prove it or start believing it works and code it. Some may say that it's essentialy brute-forcing but it shows that this problem really can be solved without using PC, which could be important during team competitions (for example your teammates have some easier problems to code in the first hour).

          Sometimes solving small cases can help you understand the structure of the problem better ;)

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    3 months ago, # ^ |
      Vote: I like it +37 Vote: I do not like it

    I think opposite. It is OK on ACM contests because you can implement bruteforce in 2 minutes, print this triangles and look at them while your teammate coding another problem.

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      3 months ago, # ^ |
        Vote: I like it -21 Vote: I do not like it

      You can get yourself a printer and print these triangles at home too :)

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3 months ago, # |
  Vote: I like it +27 Vote: I do not like it