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Amir_Reza's blog

By Amir_Reza, 2 months ago, In English,

Hello codeforces The 13 May contest will be in Your Time zone of Contest

The register will be avaibled In This time

All problems are mine and created in polygon by me

here is the link of contest : Link

register to the contest and solve problems

Thanks for joining in round !!!

UPD : Testers are sohsoh84 and funny_behradm

UPD2 : registration is open now you can register to the contest now. with this Link

UPD3 : editorial is here :

Editorial !

UPD4 : contest is finished now you can upsolve or register virtually now by this Link

Announcement of 13 May Contest
 
 
 
 
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2 months ago, # |
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Is it rated XD

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2 months ago, # |
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Auto comment: topic has been updated by Amir_Reza (previous revision, new revision, compare).

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2 months ago, # |
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Nice! :D

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2 months ago, # |
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How did you make this contest?

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    2 months ago, # ^ |
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    From polygon :D

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      2 months ago, # ^ |
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      does polygon allow us to host private contests like these?

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        2 months ago, # ^ |
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        Polygon is a platform for preparing problems in a neat and organized way. After you create a problem you can add it to a mashup here on codeforces and hold a private contest if you want.

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          2 months ago, # ^ |
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          Thanks! I didn't know that we can host private contests even if we aren't Div 1.

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2 months ago, # |
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What's the expected difficulty of problems? (in terms of Div2A, Div2B... like that)

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    2 months ago, # ^ |
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    from div5A to div1B (div2D)
    div5A div2A div2B div2C(div1A) div2D(div1B)
    my expected dificulties are not very well
    sorry for my mistake

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2 months ago, # |
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Will the tutorial be provided after the contest?

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2 months ago, # |
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Cool, I'll try your contest.
This reminded me of a local contest we created for our college recently.
Problems, written by me and one of my friend invictus_123, are worth trying for a standard div2 participant. (like me :))

Link: link to the mirror
Difficulty: div# 2
(Editorials and solutions are attached in the contest materials.)

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2 months ago, # |
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Auto comment: topic has been updated by Amir_Reza (previous revision, new revision, compare).

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2 months ago, # |
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Will we have English statements?

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2 months ago, # |
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Why don't you make the contest public in gym?

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    2 months ago, # ^ |
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    AFAIK only community members with 1900+ rating have access to that

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2 months ago, # |
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Is team participation allowed? Amir_Reza

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2 months ago, # |
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Regarding D:

why is the correct answer to 15 7 8, and not 16 31? It is not mentioned in the statement that $$$a$$$ must be less than $$$x$$$. Got WA2 before changing that.

The problems were OK, but formatting of the statements was plain horrible.

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20 mins for wa is too much lol. Nice contest btw, E was cool

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    2 months ago, # ^ |
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    Yes ;)

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    2 months ago, # ^ |
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    How did you solve E?

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      2 months ago, # ^ |
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      You can check my solution, I think it is easy, I used array period 80003087

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      2 months ago, # ^ |
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      suppose we want to have only 4 numbers

      it can be seen that the leftmost and right most number in result should be n-k

      because a + b + c + d = n and a + b + c = k => k + d = n => d = n — k

      and b + c + d = k => a + k = n => a = n — k

      => | n — k | b | c | n — k |

      then you can set b = k — n and c = k

      so you get | n -k | k — n | k | n — k |

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    2 months ago, # ^ |
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    please provide a link to your solution for question E.

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2 months ago, # |
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please make submissions visible

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2 months ago, # |
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Will you make contests again? P.S. you can make problems harder.

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Can anyone explain the solution or give proof for editorial of D.Xor Problem

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    2 months ago, # ^ |
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    k= position of leftmost set bit in ‘n’.

    ‘b’ will have the kth bit set.

    ‘a’ will have all the bits right of kth position set.

    For a^b==n we will have to set all the bits(right of kth position) in ‘b’ which are unset bits in ‘n’ and vice versa. For eg-

    n=111000011111001
    b=100111100000110
    a=011111111111111

    Only ‘b’ can have kth bit set and the largest ‘a’(a<n) we can get is when all other bits right of kth position are set(which means ‘a’ is of the form pow(2,k) — 1).

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2 months ago, # |
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Nice contest!

I thought that D and E were nice.

For better formatting there is a small MathJax reference here. You overestimated the problem difficulties by a lot. In my opinion, D and E are about Div2 B level. The others are somewhat basic. Anyway, congratulations on your contest!

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2 months ago, # |
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Testcases were weak for E. For n=1e9 and k=1 many solutions will give MLE

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2 months ago, # |
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Thank You for making contest, The questions were nice and the statements were short. But please try to make the statements more clear, They were quite confusing.

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    2 months ago, # ^ |
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    agli baar confusion ho toh iss bande se baat karna....bahut chode english hain iski...https://codeforces.com/profile/Awesome_sheK

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2 months ago, # |
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Auto comment: topic has been updated by Amir_Reza (previous revision, new revision, compare).

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2 months ago, # |
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Why did you rejudge submissios which got accepted during the contest?