ArvinCiu's blog

By ArvinCiu, 6 weeks ago, In English

logo

Halo, Codeforces! Ape kabar kitak? Nyi deu sit bau maang? 😍 😍

COMPFEST 16 is happy to invite you to participate in Codeforces Round 977 (Div. 2, based on COMPFEST 16 - Final Round) on Oct/06/2024 09:05 (Moscow time). The round will be rated. You will be given 2 hours to solve 5 problems, 2 of them will have subtasks.

Note the unusual time of the round.

The problems are written by ArvinCiu, CyberSleeper, athin, and joelgun14.

We would like to thank:

COMPFEST itself is an annual event hosted by Universitas Indonesia. It is the largest student-run IT event in Indonesia and competitive programming contest is one of the competitions hosted.

We hope you will enjoy and have fun in the contest. Muga-muga beja lan isa entuk biji apik!! 💪💪🔥🔥

Edit 1: Score distribution is $$$500 - 750 - (750+1000) - 2500 - (1750 + 750 + 1000)$$$

Edit 2:

Congratulations to the winners!

Div.2 :

  1. Xun_Xiaoyao

  2. Traumatize

  3. TurtleZW

  4. wullaaa

  5. cpy0512

Div.1 + Div.2:

  1. ecnerwala

  2. tourist

  3. ksun48

  4. StarSilk

  5. kotatsugame

Congratulations also to the first solvers!

COMPFEST team and participants

On behalf of the COMPFEST committees, we are glad that our Codeforces Round ran quite smoothly and we hope that you all enjoyed our problems. See you next year! 😍 😍

Edit 3: The editorial is up!

  • Vote: I like it
  • +384
  • Vote: I do not like it

»
6 weeks ago, # |
  Vote: I like it +30 Vote: I do not like it

Pyqe will win COMPFEST 16!

»
6 weeks ago, # |
  Vote: I like it -8 Vote: I do not like it

Please highlight the unusual starting time

»
6 weeks ago, # |
  Vote: I like it +58 Vote: I do not like it

Tomorrow:

  • 1- 4am: Hacker Cup
  • 5am — 1pm: 8 hours of good sleep
  • 2 — 4pm: Codeforces
  • 4:30pm: School

weirdest one ever

  • »
    »
    6 weeks ago, # ^ |
      Vote: I like it +20 Vote: I do not like it

    school at 4:30?

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +27 Vote: I do not like it

      China is very big country, but they use only one timeline. So if they live far from beijing, their time goes weird.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +41 Vote: I do not like it

      It's a boarding school, so we have to go back on Sunday afternoon

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it -42 Vote: I do not like it

        You don't have National Day Holiday?(In fact,I already went to school yesterday afternoon.I'm in the computer lab now.)

        As far as I know,the holiday in high school is always shorter than usual.

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          We senior high school students hardly have time to relax on holidays.

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +10 Vote: I do not like it

    based sleeping schedule

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Could you tell where to participate in Hacker Cup?

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +4 Vote: I do not like it

    Never seen such a good contest time and duration for Chinese!

»
6 weeks ago, # |
  Vote: I like it +28 Vote: I do not like it

Never seen such a good contest time and duration for Chinese!

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +2 Vote: I do not like it

    I wasn't so excited by contest. Thanks to everyone who had contributed in this contest

»
6 weeks ago, # |
  Vote: I like it +36 Vote: I do not like it

As a participant, I registered.

»
6 weeks ago, # |
  Vote: I like it +27 Vote: I do not like it

Looking forward to the contest :DDD. Thank you everyone, especially errorgorn and ArvinCiu for the sigma helps!

»
6 weeks ago, # |
  Vote: I like it +28 Vote: I do not like it

Halo Codeforces! Muga muga kowe kabeh sehat.

Maturnuwun karo KAN, errorgorn, ArvinCiu lan juru susun acara liyane uwis isa ngadano mirror COMPFEST nang Codeforces. Muga muga kowe kabeh seneng karo soale, Muga muga kowe kabeh bedja, enthuk biji sing apik, lan aja lali seneng-seneng ngelakoni ujiane.

In English
»
5 weeks ago, # |
  Vote: I like it -30 Vote: I do not like it

I am unable to attend this contest just because of the start time. Many Bangladeshi students won't be able to attend in the contest

»
5 weeks ago, # |
  Vote: I like it +16 Vote: I do not like it

What is the score distribution?

»
5 weeks ago, # |
  Vote: I like it -31 Vote: I do not like it

Never seen such a bad contest time and duration for Bangladeshi!

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +18 Vote: I do not like it

    Never seen such a good contest time and duration for Chinese!

»
5 weeks ago, # |
Rev. 3   Vote: I like it 0 Vote: I do not like it

An odd times may change anyone's rating oddly.

»
5 weeks ago, # |
  Vote: I like it +6 Vote: I do not like it

Good contest time for me.Normal contest time is "unfriendly" for boarding high school students.

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Good

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Looking forward to it.It is a CF Round which I have a time to register(which hardly ever happen).

»
5 weeks ago, # |
  Vote: I like it +5 Vote: I do not like it

Hope to reach Cyan if i managed to participate in this contest....

»
5 weeks ago, # |
  Vote: I like it +16 Vote: I do not like it

The time of the contest is so wonderful for Chinese!

»
5 weeks ago, # |
  Vote: I like it +14 Vote: I do not like it

Nice time for Chinese!

Hello (Codeforces) 2021 :)

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Cristiano Ronaldo nan paliang rancak.

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

good

»
5 weeks ago, # |
  Vote: I like it -41 Vote: I do not like it

Hope the unusual time make more people can't register, so that I can get higher rating. Hope ususual time rounds can be more and more.

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +22 Vote: I do not like it

    Bruh moment if you think less people means it's easier to get higher rating (News flash: It does not).

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +23 Vote: I do not like it

    But the unusual time makes more Chinese people register (Maybe).

»
5 weeks ago, # |
  Vote: I like it +4 Vote: I do not like it

hopefully this contest will be the start of a great journey ahead

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

when the contest will start tomorrow and how to join the contest?

»
5 weeks ago, # |
  Vote: I like it +77 Vote: I do not like it

Score distribution?

»
5 weeks ago, # |
  Vote: I like it -11 Vote: I do not like it

plz no mistakes LIKE last time...

»
5 weeks ago, # |
  Vote: I like it +8 Vote: I do not like it

Hoping for a great contest, especially with the 1am start time! Also please release the scoring distribution for the problems.

»
5 weeks ago, # |
  Vote: I like it +41 Vote: I do not like it

What about the score distribution?

»
5 weeks ago, # |
  Vote: I like it +6 Vote: I do not like it

GL & HF, and upvote for the time of the round :)

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

This is stupid, why can I only comment once in ten minutes

»
5 weeks ago, # |
  Vote: I like it +30 Vote: I do not like it

where is score distribution?

»
5 weeks ago, # |
  Vote: I like it +12 Vote: I do not like it

scoring distribution when?

»
5 weeks ago, # |
  Vote: I like it +7 Vote: I do not like it

score dist ??

»
5 weeks ago, # |
  Vote: I like it +18 Vote: I do not like it

Finally the score distribution is out!

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

AHHHHHHHHHH, continue getting TTTTtle... (4 times)

»
5 weeks ago, # |
  Vote: I like it +43 Vote: I do not like it

Is it just me or A is actually harder than B/C1 without the score distribution presented?

»
5 weeks ago, # |
  Vote: I like it +24 Vote: I do not like it

Why E3 only worth 1000 point? Isn't E1 and E2 just knapsack? Why 2500 point on them

  • »
    »
    5 weeks ago, # ^ |
    Rev. 2   Vote: I like it +3 Vote: I do not like it

    E1 could be enough for Floyd Warshall to pass. By the way, I'm surprised to hear that this is some kind of Knapsack problem.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      E2 => Knapsack

      E3 => Use Minkowski to optimize that knapsack

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

I solved A with just a hunch using priority queue, can anyone provide proof for the solution?

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +4 Vote: I do not like it

    If you do it in non-sorted order then basically, you would be making the average smaller, like if the average is non-intger then it gets rounded off. Now this rounded off number would be used for calculating the mean again and again, this way you would be affecting the largest number possible hence reducing the average by at minimum by 1. On the other hand if you via sorted order the maximum is never affected

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

D looked simple but was legit confusing once I tried solving it lol. Even E looked interesting. Welp :")

»
5 weeks ago, # |
Rev. 2   Vote: I like it 0 Vote: I do not like it

understood the issue. :)

My Disappointment Is Immeasurable and My Day Is Ruined! gg

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Is it just me, or someone else also felt like E1 is much much easier than C2 ?

( hopefully I won't get FST , my comment is based on the pretests results. May be I might be missing something which is not covered in pretest) .

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Probably... In fact coming up with idea in C1 is harder than C2 imo.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +6 Vote: I do not like it

      really?? Imo A is harder than C1, but I found C2 much harder than both.

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        Problem A, I just had some senses that if I prioritize to take those smallest numbers to do the operation, then the answer will be maximum because the larger numbers won't be halved too early. Well, you're right. Actually it's hard to prove A that way so not everyone could do it smoothly.

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          I also thought same as you can't prove the solution of A though but I think its greedy to always just chose smaller elements and that way it will be maximum

»
5 weeks ago, # |
  Vote: I like it -9 Vote: I do not like it

Speedrun.

»
5 weeks ago, # |
Rev. 2   Vote: I like it +5 Vote: I do not like it

E1 << D.

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +6 Vote: I do not like it

    I guess it was kinda obvious from score distribution

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      So it is useful to see the score distribution. (For most contests)

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

How did C2, I got the intution that we need to find inversion_count on each update but was not able to code further don't know how to find it , plz help .

  • »
    »
    5 weeks ago, # ^ |
    Rev. 3   Vote: I like it +4 Vote: I do not like it

    The sufficient condition for the order to be valid is, if you denote min_pos[i] be the minimum position the $$$i^{th}$$$ person in this order, then you need to have min_pos[a[i]] < min_pos[a[i + 1]] for all $$$1 \leq i \leq n - 1$$$. So what we can do here is maintain the number of position $$$i$$$ such that min_pos[a[i]] < min_pos[a[i + 1]]. If this number equals to $$$n - 1$$$, then the answer the Yes, or No otherwise. Submission: 284562164

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Thanks, this was the first intution before i got to inversion count , Weep :)

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      im so tilted, i came up with this with like 1 hour and 15 minutes left, and i just couldnt debug in time. thank you for the explanation

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it -7 Vote: I do not like it

        Omg bro, you're so good, it's really unfortunate that you couldn't solve the problem

    • »
      »
      »
      5 weeks ago, # ^ |
      Rev. 2   Vote: I like it 0 Vote: I do not like it

      sorted <=> no of inversions = 0 (neccessary and sufficient) , here because of permutation , we need lesser than inversions

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      an alternative for so much if statements: 284600395

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

What was the approach for C1 kept staring at it thought it as easy question and made two wrong submission then realized it's not my cup of tea. Can anyone please explain me what was the trick in the question and also share your approach. Thanks in advance.

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    The condition for the array to be good is that for every $$$a_i$$$'s first appearance in $$$b$$$, all elements that come before it in $$$a$$$ have appeared in $$$b$$$ before it.

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Basically first process all b in sequence which are unique wrt previous one, now basically you wanna check if it's elements are present in a in that order. But when there is a mismatch, this can only be fixed if that element which is now present in b has been processed sometime ago, so keep a set to keep track of all the unique elements that have been processed, if its there in set then we can rearrange it and make it feasible.

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Build an array C which only keeps first appearances, for example if b= 1 1 1 2 3 2 1, then C = 1 2 3. Then the answer is YA iff C is a prefix of the array a. After the first appearance of a student you can move him as you whish, so it only matter to compare first time of each one.

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    Just check, In what sequence members are appearing, and then check whether the members who should present each section are appearing in same order? example : 3->4->1->2 are members who will be presenting slides then, 3->3->4->1->4->3->2 is valid whereas 3->1->4->3->2 is invalid (since 1 is appearing before 4)

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    For an array $$$b$$$ to be valid, for all $$$1 \leq j \leq m$$$, the index of $$$b[j]$$$ in $$$a$$$ must be lower or equal to the number of distinct elements in $$$b[1:j]$$$.

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    I thought of if initial b order is same as a then yes else no

»
5 weeks ago, # |
  Vote: I like it +4 Vote: I do not like it

Good contest overall. Love how it requires coding knowledge to solve problems, rather than relying on obscure mathematical concepts.

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

It seems difficult to make up for the remaining questions.

»
5 weeks ago, # |
  Vote: I like it +21 Vote: I do not like it

sortforces

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Can someone explain why this submission to B fails?284540617

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Is the frec array cleared correctly?

  • »
    »
    5 weeks ago, # ^ |
    Rev. 2   Vote: I like it 0 Vote: I do not like it

    You modify $$$freq[i]$$$ for values of $$$i$$$ that are not in $$$a$$$, but only reset if for values in $$$a$$$.

    This input fails :

    input

    You should rather define vector<int> freq(n+1) in the while loop, this way you won't have to think of reseting your array.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Thank you! For some reason even after realizing only the first n values mattered I still made a global freq array. I did eventually solve it, but I didn't figure out what the mistake with this submission was.

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Can anyone tell me why I got wrong answer in this code ??

Is there any edge case I was missing ??

https://mirror.codeforces.com/contest/2021/submission/284596509

»
5 weeks ago, # |
  Vote: I like it +11 Vote: I do not like it

Good round, thanks.

»
5 weeks ago, # |
Rev. 2   Vote: I like it +11 Vote: I do not like it

Good round!!!
Thanks!!!

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

any sqrt decomp solution for C2 ?

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +23 Vote: I do not like it

    My solution used hashes. I noticed that if we leave only first occurence of each number in $$$b$$$, it must a prefix of $$$a$$$, that is both necessary and sufficient. I wanted to be able to calculate the hash of this transformation of $$$b$$$. It can be done with segment tree

    284558525 code

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      nice approach

    • »
      »
      »
      5 weeks ago, # ^ |
      Rev. 2   Vote: I like it -11 Vote: I do not like it

      Can you check my blog about this same solution? https://mirror.codeforces.com/blog/entry/134809

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +3 Vote: I do not like it

      Beautiful solution bro, I was able to boil down the problem but wasn't able to implement it.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it -8 Vote: I do not like it

      Done the same thing with hashing and seg tree

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +8 Vote: I do not like it

      I was trying to understand your code and had a few questions, in the initializer list for the parametrized constructor of the struct node, you have passed one argument to h, i.e. h(x). Looking at the constructor of the hint structure, this would mean that only h1 is set to x and h2 and h3 are still 0 right. But when you create the pref array, I believe all of h1, h2 and h3 are being set. Am I getting something wrong here?

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it +3 Vote: I do not like it

        Either c++ magic or I was actually using only one hash lol. I copied this structure from one of my previous codes and didn't give it much thought

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it +8 Vote: I do not like it

          Right, I checked locally, you're using only one hash. I really liked your idea btw, I was thinking of coming up with a hashing solution initially but I couldn't figure out how do I handle the zeros. Your idea of treating zeros as a length 0 object so that it doesn't contribute to the hash is really interesting.

»
5 weeks ago, # |
  Vote: I like it +13 Vote: I do not like it

Too tight memory limit for E2. Maybe 512MB or more would be better?

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    You need only one $$$n \times n$$$ array and some $$$n$$$ arrays, what's the need?

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      I built a Kruskal reconstruction tree which has $$$2n-1$$$ vertices, so I need one $$$2n\times n$$$ array which is too large for the memory limit.

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it +8 Vote: I do not like it

        Instead of making dp on subtrees you can merge dps of two components when Kruskal merges them

»
5 weeks ago, # |
  Vote: I like it +4 Vote: I do not like it

it was my first contest just happy to give :')

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Thank you for this round! So far my only rating loss was on COMPFEST 15, but today I got my revenge and became CM on COMPFEST 16!

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

I submitted by mistake the solution for C2 in C1 and it got accepted for C1 obviously, but the previous submission for C1 (which also passed all the test cases) was skipped and as a result my ranking declined and also my rating (seddddddd) please make the first submission for C1 only count...... ArvinCiu

284567403 got skipped and 284580672 got accepted. I want 284567403 this to be accepted instead as it was submitted well before in time than 284580672.

Thank you in advance.

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    It is the contest rule that only the final submission counts and resub gets -50

»
5 weeks ago, # |
  Vote: I like it +12 Vote: I do not like it

This round A is the same of Luogu Simulation Game

Picture:

»
5 weeks ago, # |
  Vote: I like it +10 Vote: I do not like it

I finally became an expert this round!

»
5 weeks ago, # |
Rev. 2   Vote: I like it 0 Vote: I do not like it

What's wrong with my idea in B ? My idea is to increase the frequency of $$$a[i] + x$$$ whenever the frequency of $$$a[i]$$$ is greater than 1, keep the frequency of $$$a[i]$$$ at 1, and then calculate the MEX.

from collections import Counter

def max_mex(a, x):
    freq=Counter(a)
    arr=[]
    nfreq=freq.copy()

    for k in sorted(freq.keys()):
        if nfreq[k]>1:
            nfreq[k+x]+=(nfreq[k]-1)

        nfreq[k]=1
    
    mex = 0
    while mex in set(nfreq.keys()):
        mex+=1
    return mex

t = int(input())
for _ in range(t):
    n, x = map(int, input().split())
    a = list(map(int, input().split()))
    print(max_mex(a, x))

WA Link: 284609466

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +3 Vote: I do not like it

    Consider 0 0 0 0

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Thanks, I should've read the task more clearly on "after every operation we can increment any $$$a_i$$$ by $$$x$$$. I misread as we should only able to change the original $$$a_i$$$ s. Just iterating up to $$$n$$$ would be suffice rather than iterating on freq.keys()

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    consider freq map has values [1,2] and [2,1] and x=1

    so nfreq will be same as [1,2] and [2,1] now when you are looping in freq , when 1 comes , it will inc the count of 2 in nfreq , but in freq, the count of 2 will remain same as it was previous.....so you just need to change freq to nfreq in that loop

»
5 weeks ago, # |
  Vote: I like it +3 Vote: I do not like it

I became a specialist in this round.

»
5 weeks ago, # |
  Vote: I like it +9 Vote: I do not like it

Hello guys.When will the solution be released? I think I need to add some ideas for learning how to solve problems.

»
5 weeks ago, # |
  Vote: I like it +289 Vote: I do not like it

Hi Mike, I would like to know why you have banned so many Chinese coders, I think you have mistakenly banned some of them in the same server room, and some of them have had their numbers banned but others have not, is this a mistake on your part?

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it -664 Vote: I do not like it

    They all used secondary accounts to participate in today's round. Such behavior is unacceptable and violates the rules. I think this could be a good lesson. I spent the entire two hours of the round investigating and analyzing the situation because of these "jokers".

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +123 Vote: I do not like it

      So they got their solutions skipped or did you just remove them from official standings?

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +61 Vote: I do not like it

      But you only banned a few people, there are still a lot of people who weren't banned, isn't that a mistake on your part?

      • »
        »
        »
        »
        5 weeks ago, # ^ |
        Rev. 3   Vote: I like it -517 Vote: I do not like it

        No, it isn't Mike's fault. It's the owner of those accounts to blame. Also, don't make these meaningless accusations, especially when you don't have any contribution to the community. If you think there are other accounts that should be banned, you could tell Mike kindly.

        For those who can neither speak English nor show their courtesy in their comments, I feel sorry for their country for having such a group of low-quality coders. (FYI: This is not for ChatgptMini, it's to the commenter of the abusive words in Chinese which got removed afterward)

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it +272 Vote: I do not like it

          You can not show your courtesy,too.

          • »
            »
            »
            »
            »
            »
            5 weeks ago, # ^ |
              Vote: I like it -370 Vote: I do not like it

            Yes, and yet it has nothing to do with what I said.

            • »
              »
              »
              »
              »
              »
              »
              5 weeks ago, # ^ |
                Vote: I like it +136 Vote: I do not like it

              Why don't you think about why you've got 16 down? Think about what you're saying.

              • »
                »
                »
                »
                »
                »
                »
                »
                5 weeks ago, # ^ |
                  Vote: I like it +57 Vote: I do not like it

                They criticised Chinese alters and got downvoted, wow. Seriously, why do Chinese give alters a pass? I'm also a Chinese and I don't condone such behaviour.

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it +155 Vote: I do not like it

          Firstly, I don't think it's embarrassing to not know English. Secondly, when you do not have enough community contribution, you should not use community contribution to evaluate this matter.

          • »
            »
            »
            »
            »
            »
            5 weeks ago, # ^ |
              Vote: I like it -218 Vote: I do not like it

            Firstly, I don't think it's embarrassing for not knowing English, either. But I think it's improper to use Chinese to post comments (especially abusive ones) when the only allowed languages are English and Russian.

            Secondly, I don't see there's a connection between my own contribution and the matter I'm talking about.

            • »
              »
              »
              »
              »
              »
              »
              5 weeks ago, # ^ |
                Vote: I like it +99 Vote: I do not like it

              What I mean is, you shouldn't differentiate people based on community contributions. Moreover, I believe that Mike's behavior also contains certain errors, and the punishment for opening a small account should not be imposed on a large account, which is extremely unreasonable.

              • »
                »
                »
                »
                »
                »
                »
                »
                5 weeks ago, # ^ |
                  Vote: I like it -148 Vote: I do not like it

                What I wanted to say is if he thought there are some accounts Mike forgot to block/unblock, he could tell Mike. I believe this is the better way to contribute to the community instead of blaming Mike. Sorry if I caused any confusion.

              • »
                »
                »
                »
                »
                »
                »
                »
                5 weeks ago, # ^ |
                Rev. 2   Vote: I like it +17 Vote: I do not like it

                Are you supposing that the owners of your alts are not you? The one to be punished is you instead of your account, although the sudden ban without any warning is somehow annoying and unreasonable.

                • »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  5 weeks ago, # ^ |
                    Vote: I like it +30 Vote: I do not like it

                  But the punishment should correspond to the behavior, not the owner of the account. The act of registering a small account has nothing to do with a large account.

            • »
              »
              »
              »
              »
              »
              »
              5 weeks ago, # ^ |
                Vote: I like it -124 Vote: I do not like it

              There is some stupid mass attack from Chinese users. All comments opposing their cheating are getting downvoted. Maybe they should try following the rules next time.

              • »
                »
                »
                »
                »
                »
                »
                »
                5 weeks ago, # ^ |
                  Vote: I like it +32 Vote: I do not like it

                That's not true. We're not cheating.

                • »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  »
                  5 weeks ago, # ^ |
                    Vote: I like it 0 Vote: I do not like it

                  Chinese are not cheating but you're not Chinese……

              • »
                »
                »
                »
                »
                »
                »
                »
                5 weeks ago, # ^ |
                  Vote: I like it +1 Vote: I do not like it

                Fox dung to that. Do you really believe your community, whatever it is,have no cheaters? Think of that before you speak

              • »
                »
                »
                »
                »
                »
                »
                »
                5 weeks ago, # ^ |
                  Vote: I like it +1 Vote: I do not like it

                The cheaters cheated. Not the mass Chinese users.

              • »
                »
                »
                »
                »
                »
                »
                »
                5 weeks ago, # ^ |
                  Vote: I like it +5 Vote: I do not like it

                We are not cheating!Most of Chinese users are really strong.The cheaters cheated.Just like rapists rape women.But not all Indians rape women.

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
          Rev. 3   Vote: I like it -27 Vote: I do not like it

          This blog were deleted...

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it +52 Vote: I do not like it

          I think you are the biggest joker.

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it +20 Vote: I do not like it

          No, it isn't Mike's fault. It's Mike's and your fault.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +69 Vote: I do not like it

      Will these people's accounts be unblocked after a period of time?

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it -13 Vote: I do not like it

      If you don't have an idea how to reconcile with the remote judge of Luogu or to solve the cloudflare and DDOS problems of codeforces, then you don't have an idea how to go home.

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it +34 Vote: I do not like it

        MikeMirzayanov

        Healthy humans are supposed to break out of the solar system.

        The goal should be clear.

        You can go home if you have no idea.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +14 Vote: I do not like it

      Agreeing with the rules, but I would like to see if random people with multiple accounts are investigated, analyzed and banned, but not only the tops of the rank list. Otherwise, it is still unfair and amusing. Let alone if the rule is set reasonably.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +26 Vote: I do not like it

      Thanks to Mike, we now have a great CP site with bad connection (for all the users) but more importantly, good discipline (for some of the alt users)! Which is the most important is obvious for everyone! sto MikeMirzayanov orz

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it -14 Vote: I do not like it

        Lets cheer, for today is the day Mike spent 2h dedicated on such meaningful work!

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +257 Vote: I do not like it

      why use alt got banned but cheaters just got skipped?

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +48 Vote: I do not like it

      Then you shouldn't ban large accounts either, as it will make the efforts of many users in vain.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Man, what can I say?

      74traktor and mike out!

    • »
      »
      »
      5 weeks ago, # ^ |
      Rev. 2   Vote: I like it +26 Vote: I do not like it

      I agree with the rule, but I want to see more proof of it.

      I think some people have been wronged.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it -94 Vote: I do not like it

      Hey! Why giving mike downvotes? Has he done anything wrong? Let's upvote!

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it +29 Vote: I do not like it

        Whether we downvote or upvote is decided by the content of the text, not by the sender.

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it -9 Vote: I do not like it

      • »
        »
        »
        »
        4 weeks ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        no fishing.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +47 Vote: I do not like it

      i agree with the rule, but i think you maybe wrongly banned some of them because in China there are few IPs and many people are using the same IP to surf the Internet.

      to MikeMirzayanov

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Could you please show the method to tell whether the accounts are of the same person?

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it -22 Vote: I do not like it

      That is to say, you should also ban orzdevinwang because he used zh0ukangyang account before. MikeMirzayanov

    • »
      »
      »
      5 weeks ago, # ^ |
      Rev. 23   Vote: I like it -38 Vote: I do not like it

      MikeMirzayanov

      麦克 蜜耳炸压懦夫

      You are joker.

      你是小丑。

      qijianci said.

      萎哥说。

      Your biggest mistake is to ban wo_shi_wei_ge during the game!

      你最大的错误就是在赛时封禁了”我是萎哥“!

      You will regret it for the rest of your life!

      你会后悔一辈子的!

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it -10 Vote: I do not like it

      Laugh track analysis: laugh track analysis deleted

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +15 Vote: I do not like it

      Yeah some people have violated the rules.But they are not "jokers" at all.

      About the impolite comments the other people said,I feel sorry and ashamed.

    • »
      »
      »
      5 weeks ago, # ^ |
      Rev. 2   Vote: I like it +23 Vote: I do not like it

      In China, if someone cheating in competitions, there will be a ban about only accounts which participate in cheating. It can be fifty or more people who using the same IP, so you should not punish by banning IP addresses, as this may affect many innocent people  Others are not obligated to take responsibility for cheating, even if their IP addresses are the same  

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it -38 Vote: I do not like it

      Why Why Why,Why Why Why,Why is the punishment for people with trumpets worse than people who cheat, do you have any ideas, if you don't you can just go home

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it -43 Vote: I do not like it

      Don't think you're an administrator you can just slander people, don't talk shit about people because you can't do it. You have no evidence! !!! codeforces, that is the administrator enjoys the highest power, you think I am copying, you brown it, you can even block my number. But the eyes of the masses are bright !!!!

      If you block me, it will let the oiers of the whole world know that codeforces admins are rotten!!!! codeforces will be infamous!

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +16 Vote: I do not like it

      Your recent complaint has been reviewed and found to be clearly unjustified. Submitting such complaints violates the Codeforces rules—this is clearly stated right in the complaint submission form. As a punishment, you are barred from submitting complaints for 7 days. Repeat violations will lead to more severe measures, up to and including the blocking of your account. Please do not submit any more unjustified complaints.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +11 Vote: I do not like it

      How do you know? If a lot of classmates participate in their school's special computer room, they would have the same IP.

»
5 weeks ago, # |
Rev. 2   Vote: I like it 0 Vote: I do not like it

Can somebody please explain the solution of E1?

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +8 Vote: I do not like it

    You can use Floyd- Warshall to create a distance matrix of the maximum of all edges used to reach that node and then greedily pick the server that gives the lowest sum across all houses that need internet because constant is small.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      But how do you pick 2 optimal servers, then 3 optimal servers efficiently?

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        Run 3 nested loops : one for each additional server, then on all nodes, then for houses that need internet. You also need a visited array for servers chosen already.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +36 Vote: I do not like it

      Why is it true that if we pick a server for k, it will be choosen for a bigger k?

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it -8 Vote: I do not like it

        Greedily, it always makes sense to select one of the p nodes as the server ... Hence, when a node is chosen for k it remains.

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it +10 Vote: I do not like it

          Seems to me that it doesn't work that easily, guys. Sometimes it's hard to prove greediness, and I didn't see proof in your answers. Maybe, I'm missing something so answer, plz, to the following question.

          For example, if we install server in vertex 3 for k=1, then why it's not possible for k=2 to have set of vertices (1, 2) as an optimal solution with latency less than (3, 1) or (3, 2) or any other (3, *)?

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it +3 Vote: I do not like it

          It's easy to prove that it's always optimal to choose one of the p nodes (if we have solution with server in node v which is not in one of the p nodes, we can choose node w which is p node and minimalizes maximum on the path from v to w, then move server from node v to node w and we have solution equal or better), but i don't know why do nodes remain when they're choosen

»
5 weeks ago, # |
  Vote: I like it +5 Vote: I do not like it

Can anyone help me with problem a , I wasted a lot time but couldn't come up with some with good logic

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    my idea was that the last element will be max, if the previous two elements that make it are max. so how would you pair so that this happens?

    1.pairing anything with the max element only decreases the max element. so not advisable. 2. pair min with min? yes! it increases the overall min of the array without hurting the max.

    so, sort the array and pair min with min.

    284608545

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    I used priority queue (min heap) & kept taking floored average of 2 smallest nos., popping those 2 from the queue, & pushing back the floored average, until just a single number was left in the queue. You can view my solution.

»
5 weeks ago, # |
  Vote: I like it +28 Vote: I do not like it

As an official contestant, I just wanna say that "Boss, Thirsty" and "Digital Village" are very cool problems! Congrats to the problemsetters!

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Can anybody help me find what's wrong with my solution for B ? 284594624

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Try > 1 instead of > 0

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Unfortunately it didn't work, rep stores the number of repetitions in my case not the number of instances.

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    okay so after a lot of headache i figured it out.

    the problem with my code was that it basically was only checking for "gaps" between numbers within the array. but it didn't try to fill the gaps after the largest array element.

    adding a while loop that tries to complete the array after the largest element using the same idea in the previous loop seemed to work.

»
5 weeks ago, # |
  Vote: I like it +15 Vote: I do not like it

When will the editorial come out? I would like to see the solution for problem D and E3.

»
5 weeks ago, # |
  Vote: I like it +4 Vote: I do not like it

Tutorial when? QwQ

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Anybody else missed the round?

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

How C2?

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +3 Vote: I do not like it

    3 2 1 4 — array a

    1 3 3 2 1 2 4 1 4 — array b

    so positions in sorted order in array b for each integer :

    3 : 2 3

    2 : 4 6

    1 : 1 5 8

    4 : 7 9

    If and only if bold letters are sorted from top to bottom then YA otherwise TIDAK

    Try to think from here

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      I had this exact idea and 40 min left in the contest. But couldn't figure out at all how to check if they are sorted or not in O(logn). Any hints or ideas?

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it +4 Vote: I do not like it

        segment tree? I could not think other solution.

      • »
        »
        »
        »
        5 weeks ago, # ^ |
        Rev. 3   Vote: I like it 0 Vote: I do not like it

        after each update only two bold letter's values get changed , so it's sufficient to only check those two bold letters and the ones immediately after that total 4 , keep a $$$track[i]$$$ which says whether bold letter in $$$i$$$ > bold letter in $$$i - 1$$$ and also keep count of no of $$$track[i]=1$$$ on the flow

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it +1 Vote: I do not like it

        You can use a heap to store the slides for each member. After any change, it's easy to pick the new earliest slide the user needs to present(it's just the top of the heap). This can be used to maintain an array of first slide, each member in the queue needs to present. If that array is sorted, the slides are presentable. We can keep track of number of indices where a[i+1] < a[i] after each query, for a sorted array, this would ofc be zero.

        Code(Python), fairly readable - https://mirror.codeforces.com/contest/2021/submission/284731038

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

I sort of understand the solution of B. But I keep getting TLE and I don't know how to optimize it. Can someone help me look at my code? It is 284575211. It should be pretty readable and it is basically brute force. Thanks a lot!

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Switch unordered set to a vector with size n and it should work.

    • »
      »
      »
      5 weeks ago, # ^ |
      Rev. 2   Vote: I like it 0 Vote: I do not like it

      Thank you for the suggestion. I have tried to implement it with vector using the same idea and it did pass a few more test case. But still got TLE at testcase 9 284649489. I would appreciate any more suggestions.

      Edit: Actually I changed a few long long int to int and it passed but barely rt: 0.9(s). Is there a better way of tackling this problem?

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        try inputting all numbers before actually doing any operations, it should be much faster that way

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          Thanks it worked!! Is there an explaintion for that? Or should I just avoid doing operations while inputting?

          • »
            »
            »
            »
            »
            »
            5 weeks ago, # ^ |
              Vote: I like it 0 Vote: I do not like it

            this way youre iterating n times exactly, so it cant TLE, in your previous approach for some inputs, you sometimes iterate over numbers redundantly,which leads to tle

  • »
    »
    5 weeks ago, # ^ |
    Rev. 2   Vote: I like it 0 Vote: I do not like it

    In your solution, the value is pushed forward until it becomes unique.

    Then consider the following test.

    1

    200000 1

    99999 99998 99997 ... 0 0 0 ... 0

    In this case, there will be no pushing until the first zero appears, but the remaining $$$10^5$$$ zeros will pass through all values greater than 0, which are also $$$10^5$$$ at the very beginning.

    Thus, at least $$$10^{10}$$$ operations will be performed in total, which is why TLE occurs, and the asymptotics of this solution is $$$O(n^2)$$$

    • »
      »
      »
      5 weeks ago, # ^ |
      Rev. 2   Vote: I like it 0 Vote: I do not like it

      Thank you I understand. How should I optimize the solution? Basically how would I skip those numbers for a faster run time?

      Edit: I have a new solution that passed but the runtime wasn't great. Maybe there is a better way of dealing with this problem? 284650265

      • »
        »
        »
        »
        5 weeks ago, # ^ |
        Rev. 2   Vote: I like it 0 Vote: I do not like it

        I wrote my own editorial for this problem in this comment, the asymptotics of the solution is O(n)

»
5 weeks ago, # |
  Vote: I like it +2 Vote: I do not like it

Why still no editorial

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

getting wrong ans on test case 2(C1) please point out the error in my code 284584744

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

someone explain B

  • »
    »
    5 weeks ago, # ^ |
    Rev. 3   Vote: I like it +3 Vote: I do not like it

    Let A be the initial array. Note that the maximum MEX cannot be greater than n, since there are n total elements in the array. Let the array C contain the number of elements with the value Y in the array C[Y] = k, where Y is the value of the element, k is the number of Y in A (Since MEX is not greater than n, then it makes no sense to store Y > n values in C).

    Initially, we will go through the array A and for each of its elements $$$Z < n$$$ we will make C[Z] += 1.

    Now let's see which element we can't get in A. Let it be the element $$$el$$$

    Initially, $$$el = 0$$$. Next, we will use the following algorithm.

    If $$$el \ge x$$$ and $$$C[el - x] > 0$$$, then C[el] += C[el-x]-1. If we have several identical values, then it is optimal to change all but one, because MEX will not became lower from this. Using the C array, we push the elements further, leaving only unique values behind.

    If $$$C[el] > 0$$$, then el += 1, otherwise we will not be able to get the value of $$$el$$$ in the array A, which means the maximum MEX will be equal to $$$el$$$

    The asymptotics of such a solution is O(n)

    Edit: Code of this solution — 284652327

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      I understand now thank you. I am supposed to move all duplicates at once instead of one by one.

»
5 weeks ago, # |
  Vote: I like it 0 Vote: I do not like it

Just woke up from my long slumber(my brain crashed while giving my worse possible Hacker cup, so I had to) and was looking for the Codeforces contest, and realizing only now, I have already missed it

»
5 weeks ago, # |
  Vote: I like it -11 Vote: I do not like it

anyone solved C2 with merge tree ?

»
5 weeks ago, # |
Rev. 2   Vote: I like it +7 Vote: I do not like it

nvm

»
5 weeks ago, # |
  Vote: I like it +5 Vote: I do not like it

Can somebody help me with my code for B? Why does it fail. Cannot seem to find any counter test case on my own — Link to code

  • »
    »
    5 weeks ago, # ^ |
      Vote: I like it +3 Vote: I do not like it
    1
    5 1
    0 0 0 1 1
    
    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it +10 Vote: I do not like it

      Thanks for pointing the test case my code gives 4. It should have been 5. Can you please guide what am I missing.

      • »
        »
        »
        »
        5 weeks ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        You don't consider case when after moving elements there is number x that wasn't in the initial array and freq[x] > 1. You should move this element too, in your loop you only check elements that were in initial array.

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it +10 Vote: I do not like it

          Hey Thanks. Got the problem solved it by replacing vec[i] with just i. After your explanation.

»
5 weeks ago, # |
  Vote: I like it +46 Vote: I do not like it

We are still waiting for the Editorial :(

»
5 weeks ago, # |
  Vote: I like it -25 Vote: I do not like it

Mike,please tell me,why do cheaters only get skipped while using multi accounts is getting banned?(plz forgive my poor English.)

  • »
    »
    5 weeks ago, # ^ |
    Rev. 3   Vote: I like it -14 Vote: I do not like it

    Ask yourself,

    1) How many Voter cards you have ?

    2) How many LinkedIn Profile you have ?

    3) How many Students Profile you have at your college / school ?

    Now, one may argue, codeforces is neither voting platform, nor hiring platform or may be school. But, this is some other platform, we want to keep fairness. We want to keep single identity for one person.

    4) What do we achieve by keeping one account ?

    TRANSPARANCY and FAIRNESS.

    So many of the Chinese CP-athelets are ORZ. Only a fool would doubt that. Now, these ORZ-Chienese CP-athelets are already in Div-1 at codeforces. They create ALT accounts and gets higher ranks and the person who should get rank below 200, actually gets rank above 500-700 ( considering 400-500 alt accounts ).

    Now, coming to CHEATERS. They suck. They don't have brains. Some people cheat because they are looking for job opportunities. In India, if you are college student, one of the criteria for getting interview opportunity is, you have good rating on coding platforms.

    Cheaters suck, so do ALT account users.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it -19 Vote: I do not like it

      You are right, but I think cheating is more severe than having alt accounts.

    • »
      »
      »
      5 weeks ago, # ^ |
        Vote: I like it -22 Vote: I do not like it

      I see.However,skipping is in order to warn the cheaters before banning them,but alt accounts users DON'T get warned before they get banned.

      So why don't just ban accounts that were rigistered later but ban their all?

      Definitely cheating is more terrible than using alt accounts,but what mike is doing is like alt is more terrible.

      • »
        »
        »
        »
        5 weeks ago, # ^ |
        Rev. 2   Vote: I like it -14 Vote: I do not like it

        What do you suggest to do here ?

        Should we warn the ALT account user ? How do we do it ? How does codeforces know, which two accounts are owned by same user ?

        If your government knows, you have two passports, then government will invalid one of the passports. Either you get notice or default. In case of codeforces, we don't have any other option to send notice or anything.

        I simply fail to understand, WHY DO YOU NEED ALT ACCOUNT ????

        are you trying to hide from others that you are still coding ? ( may be the solution to this problem is, codeforces provide some hide-profile mode )

        • »
          »
          »
          »
          »
          5 weeks ago, # ^ |
            Vote: I like it +1 Vote: I do not like it

          Then why do codeforces warn cheaters(by skipping) but not just ban them?

          • »
            »
            »
            »
            »
            »
            5 weeks ago, # ^ |
            Rev. 2   Vote: I like it -16 Vote: I do not like it

            You can ban them. Lack of awareness, or lack of knowledge, or may be pressure to get job makes people cheat.

            But literally everyone makes mistake. If the mistake is repeated multiple times, then of course you should get banned.

            Forgiveness is your answer !!!

            I don't know about others, but I believe in second chances.

            • »
              »
              »
              »
              »
              »
              »
              5 weeks ago, # ^ |
                Vote: I like it +17 Vote: I do not like it

              You give the second chance to cheaters,then why not give it to alt users?