duality's blog

Codeforces Round #884 (Div. 1 + Div. 2)
By duality, history, 3 years ago, In English

Hello, Codeforces!

I invite everyone to participate in Codeforces Round 884 (Div. 1 + Div. 2), which will start on Jul/11/2023 17:35 (Moscow time). The round is a combined round and will be rated for everyone.

You will be given 8 problems and 3 hours to solve them. One of the problems is divided into two subtasks. The scoring distribution will be:

$$$500$$$ — $$$1000$$$ — $$$1250$$$ — $$$1500$$$ — $$$2000$$$ — $$$(2000+1000)$$$ — $$$3500$$$ — $$$4000$$$

All problems are written and prepared by me. I would like to thank:

I look forward to your participation and hope you enjoy the problems. Good luck!

UPD 1: Editorial

UPD 2: Congratulations to the winners!

  1. cnnfls_csy
  2. tourist
  3. DearMargaret
  4. ksun48
  5. gyh20
  6. heno239
  7. jiangly
  8. ecnerwala
  9. neal
  10. Sugar_fan

and congratulations to cnnfls_csy and orz for solving problem H!

  • Vote: I like it
  • +1077
  • Vote: I do not like it

Comments Comments (294)
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3 years ago, hide # |
 
Vote: I like it +29 Vote: I do not like it

Now the testers can comment

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3 years ago, hide # |
 
Vote: I like it +61 Vote: I do not like it

As a tester, I comment

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3 years ago, hide # |
 
Vote: I like it +98 Vote: I do not like it

It's amazing that a single writer prepared all the problems for a Div. 1 + Div. 2 contest! Hope the problems are interesting :)

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3 years ago, hide # |
 
Vote: I like it +6 Vote: I do not like it

Looking forward! Score distribution means I might finally get a D solve again ;)

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3 years ago, hide # |
 
Vote: I like it +50 Vote: I do not like it

Is the cat in Golovanov399's profile coughing?

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3 years ago, hide # |
 
Vote: I like it +40 Vote: I do not like it

As a tester, I can confirm the hardest problem is harder than the easiest one.

Good luck!

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3 years ago, hide # |
 
Vote: I like it +6 Vote: I do not like it

hope to become green in this contest.

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3 years ago, hide # |
 
Vote: I like it -12 Vote: I do not like it

Why is problem number 6 score (2000+1000)? Is it because of subtasks? Asking because I have never seen subtasks on CF :)

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3 years ago, hide # |
← Rev. 3  
Vote: I like it -11 Vote: I do not like it

One good contest for me and I will be surely on my peak.

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

As a tester, video editorials for most problems will be on my channel after the contest

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3 years ago, hide # |
 
Vote: I like it +4 Vote: I do not like it

Hoping to reach blue

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3 years ago, hide # |
 
Vote: I like it +113 Vote: I do not like it

I was just wondering, is there a reason why this round is combined Div.1 + Div.2, while the rounds are usually separate Div.1 and Div.2? I understand that rounds with prizes are combined to let everyone have a chance for a prize but this round is not one of those.

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Here we go, Go to Grey again :)...

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3 years ago, hide # |
 
Vote: I like it +8 Vote: I do not like it

can anyone tell me how can I become a tester?

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3 years ago, hide # |
 
Vote: I like it -8 Vote: I do not like it

are you from the same London as Justin Bieber?

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3 years ago, hide # |
 
Vote: I like it -93 Vote: I do not like it

I thinks that frequency Of DIV : 4 contest is reduced so much??? As earlier DIV : 4 almost happen every month But of now there is no DIV : 4 contests happening.... It's very long time that No DIV : 4 contest has been happened....If it is like this what will happen to the participants like us which are "newbie" on codeforces... Isn't It?? What's Your opinions On this... Just personal Feeling's.. If anyone get's offended by this Sorry for that(:

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Is +66 delta too much to ask for!!!

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3 years ago, hide # |
 
Vote: I like it -7 Vote: I do not like it

As a partcipant, I excited

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Enjoy the three hours and get rating

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3 years ago, hide # |
 
Vote: I like it +2 Vote: I do not like it

Question:

Sir, I am a newbie. So am I eligible for this contest ?

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3 years ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

Hope to get close to CM :)

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Tonight, I am ready for the first battle to achieve the prestigious Purple Rank.

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3 years ago, hide # |
 
Vote: I like it -6 Vote: I do not like it

I will try to solve A-D ASAP to have time to solve E, sound interesting!

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3 years ago, hide # |
 
Vote: I like it +4 Vote: I do not like it

I'm sad. I have a summer camp so I can't participate. I will definitely up-solve the problems in the contest tho. To everybody who is taking the contest, GL & HF!!!

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3 years ago, hide # |
 
Vote: I like it -8 Vote: I do not like it

I wish I can see a Lockout Between tourist and Benq :) ... What is ur opinion guys ?

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3 years ago, hide # |
 
Vote: I like it +1 Vote: I do not like it

I hope we don't go back to the green name

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Does this mean that our ranking will be more than 1,000 lower than the usual Div.2, and it will be more difficult to add points, because the experts of Div.1 will also participate.

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

poorpul

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

i wanted to see tourist at 1 again.

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3 years ago, hide # |
← Rev. 2  
Vote: I like it 0 Vote: I do not like it

wait i cannot register anymore, why? Edit: i tried to register 10 mins before contest

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3 years ago, hide # |
 
Vote: I like it +14 Vote: I do not like it

Slowly proceeding towards my fav colour :)

and it is
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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

is cf-predictor working? it's not working for me

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3 years ago, hide # |
 
Vote: I like it +4 Vote: I do not like it

i am going to get demoted for sure.

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3 years ago, hide # |
 
Vote: I like it -9 Vote: I do not like it

DsolvingForces

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3 years ago, hide # |
 
Vote: I like it -20 Vote: I do not like it

Balanced as everything should be ):

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3 years ago, hide # |
 
Vote: I like it +41 Vote: I do not like it

speedforces

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3 years ago, hide # |
 
Vote: I like it -18 Vote: I do not like it

Wow,5500 submissions on problem D,codeforces has become leetcode. Cheaters everywhere.

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3 years ago, hide # |
 
Vote: I like it -11 Vote: I do not like it

Rating is not increasing ,neither the contributions, what should I do now ?

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3 years ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

Problem A

May I know why this condition is not valid

if(a == 1){
    cout << 2 << '\n';
} else {
    cout << 1 << '\n';
}
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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

ConstructiveForces

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3 years ago, hide # |
 
Vote: I like it +209 Vote: I do not like it

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3 years ago, hide # |
 
Vote: I like it -8 Vote: I do not like it

How to solve C?

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    3 years ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    It's not possible to sum odd and even index numbers. Try it.

    So you have to get max sum from either odd or even index numbers.

    The odd (in this case) can be summed up (or deleted) and the even have to be deleted. And vice versa.

    Also check for the case when all numbers are negative.

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

so what was the edge case for C?

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3 years ago, hide # |
 
Vote: I like it +61 Vote: I do not like it

Codeforces Round #884 (Div. 1 + Div. 2)
ConstructiveForces

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3 years ago, hide # |
 
Vote: I like it +15 Vote: I do not like it

Speedforces from A to D

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3 years ago, hide # |
 
Vote: I like it +49 Vote: I do not like it

teach me E

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3 years ago, hide # |
 
Vote: I like it +33 Vote: I do not like it

Why does every problem in this contest feel constructive? 🤡

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3 years ago, hide # |
 
Vote: I like it -17 Vote: I do not like it

Problem E is cool!

Though ABCD were absolute speedforces which I really failed, after solving E it didn't matter

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3 years ago, hide # |
 
Vote: I like it +22 Vote: I do not like it

Swap(C,D), D was very straightforward unlike C.

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3 years ago, hide # |
 
Vote: I like it +55 Vote: I do not like it

so huge gap between D and E

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3 years ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

Great contest! 2 problems with hello world solution is insane :D

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3 years ago, hide # |
 
Vote: I like it +125 Vote: I do not like it

GuessForces

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    3 years ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    Please explain E.

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      3 years ago, hide # ^ |
      ← Rev. 3  
      Vote: I like it +8 Vote: I do not like it

      I guessed the solution of E but don't know how to prove it.

      For (i, j) such that 1<=i<=n-1, 1<=j<=m-1, we must have (i, j)==(i+1, j+1) (we denote a[i][j]=0) or (i+1, j)==(i, j+1) (we denote a[i][j]=1), then for any valid grid, there must be some f[i] and g[j] such that a[i][j]=f[i] xor g[j]. Then we can solve the problem by dsu.

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        3 years ago, hide # ^ |
         
        Vote: I like it 0 Vote: I do not like it

        I have been thinking for an hour but still cannot come up with a conclusion, can you give me a rough idea?

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          3 years ago, hide # ^ |
          ← Rev. 2  
          Vote: I like it 0 Vote: I do not like it

          think not about the letters, but about the grid of choice which diagonal contains the same elements in 2x2 squares — 1/0. All the lines of the grid are the first or the reversed first (suppose you know the first row and the first element of the second — you will see that the second is uniquely restored). Then check if it is possible — a system of disjoint sets and a top-down/left-to-right scanline

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            3 years ago, hide # ^ |
             
            Vote: I like it 0 Vote: I do not like it

            apparently, the second part can be made much easier :)

            (Editorial is already out)

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              3 years ago, hide # ^ |
               
              Vote: I like it 0 Vote: I do not like it

              Can I ask how you found this pattern? I couldn't construct objective examples for me to observe during the competition. Did you figure it out just by looking at the samples?

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                3 years ago, hide # ^ |
                ← Rev. 2  
                Vote: I like it 0 Vote: I do not like it

                in samples there is "square"

                1 ... 1

                .......

                1 ... 1 — YES

                1 ... 1

                .......

                0 ... 1 — No

                from that and looking at n = 3 m = 3 cases

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3 years ago, hide # |
 
Vote: I like it +18 Vote: I do not like it

shout out to ur mom and ur 1e9 copies for problem E

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

As a leetcode refuge, I really enjoy these problems, even if I solve a few each time. I can feel my brain working ;p. Each problem seems so easy after I finally solve it, but before that I might spend an hour on it.

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3 years ago, hide # |
 
Vote: I like it +5 Vote: I do not like it

Amazing contest! Had fun solving A to D, each problem had some beautiful insight hidden — which apparently, I was too dumb to notice, hence overkilled A with DP :X

Cheers to -100 delta, and 3 hours of absolute fun! Kudos to the author, and the entire team. Looking forward to future contests by duality!

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    3 years ago, hide # ^ |
     
    Vote: I like it +3 Vote: I do not like it

    No way you used dp on problem A hahaha. Btw, it is always helpful to check the leaderboard. If a lot of people are getting AC on a given problem and you are stuck on it, chances are the solution is much easier than it seems.

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Someone tell me how to solve "B. Permutations & Primes" problem?

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    3 years ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    Anything that includes 1 and 2, but doesn't include 3 has prime MEX. So we place 1 and 2 in the middle and 3 all the way to the side, to maximize number of such segments.

    Now, anything that doesn't include 1 can't have prime MEX, so now we only need to consider segments that contain 3 and 1. The only way this can fail to have prime MEX is if it includes 2 but not 4. So, we place 4 right next to 3 to minimize such segments. Now. We only need to consider segments that contain 1 2 3 and 4. These have prime MEX unless they contain 5, so we place 5 all the way to the other side of 3 and 4.

    After this you can fill in the rest of the numbers arbitrarily.

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

I did not partecipate the contest but I Will try to upsolve. I think problem C can be done through DP. Is this the right way to go?

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3 years ago, hide # |
 
Vote: I like it +1 Vote: I do not like it

E destroyed my brain

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3 years ago, hide # |
 
Vote: I like it +114 Vote: I do not like it

What a gem of a round! E and G are just stunning problems, and the rest is very good also.

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3 years ago, hide # |
 
Vote: I like it +19 Vote: I do not like it

c>>>>>>d anyone?

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3 years ago, hide # |
 
Vote: I like it +8 Vote: I do not like it

coloringforces

anyway, it was a nice contest, really liked the problems :D

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3 years ago, hide # |
 
Vote: I like it +1 Vote: I do not like it

Wow! Superfast editorial with hints..

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3 years ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

I think C > D......

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3 years ago, hide # |
 
Vote: I like it +12 Vote: I do not like it

want more frequency in contests

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

blazzing fast editorial

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3 years ago, hide # |
← Rev. 2  
Vote: I like it +21 Vote: I do not like it

Maybe testdata of F1 and F2 is too weak? My O(n^2) solution for F1 successfully passed F2. https://mirror.codeforces.com/contest/1844/submission/213394774

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    3 years ago, hide # ^ |
     
    Vote: I like it +18 Vote: I do not like it

    and to my surprise, it even faster than most of O(nlogn) solutions.

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      3 years ago, hide # ^ |
       
      Vote: I like it +33 Vote: I do not like it

      Hacked. A case containing lots of gaps that are less than $$$|c|$$$ but where twice the gap is more than $$$|c|$$$ causes your code to repeatedly erase from the front of the list, achieving $$$\mathcal{O}(n^2)$$$ behaviour.

      Unfortunately, I did not anticipate this approach before the round, so the tests did not contain this type of case.

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3 years ago, hide # |
← Rev. 3  
Vote: I like it +33 Vote: I do not like it

Good problems and strong pretest! I ranked 377 when the contest ends, and rank 377 after the system test. The only thing needs to mention is that difficulty gap between D and E is too large.

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

I hope to become an expert：）

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3 years ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

I really enjoyed solving problems of this round, problem C is my favourite problem now, it is very interesting. But i have a problem, I have "hack it" button after the ending of the round

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3 years ago, hide # |
 
Vote: I like it +26 Vote: I do not like it

orz Orz

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

I am trying to figure out what is wrong with my solution https://mirror.codeforces.com/contest/1844/submission/213344967

It appears that the checker output does not show failed test case. Is it intentional? If so why is that?

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    3 years ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    I think from one of the odd or even sets we have to take only positive charges in your solution according to my thinking you are considering the sum as maximum(ith charge or sum + ith charge ) but if ith charge is -ve we dont have to consider it

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    3 years ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it 
    1
5
5 1 -4 2  6

    output should be 11. your code gives 7.

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      3 years ago, hide # ^ |
       
      Vote: I like it 0 Vote: I do not like it

      Thank you for provided test case, but what I actually want to know is why failed test cases are not shown in checker output.

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

no offence but why A to D has to be easy speed forces in a div-1 + div-2 round ?

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3 years ago, hide # |
 
Vote: I like it +20 Vote: I do not like it

Div.1+ div.2 = div.3

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

B>C for me

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Did anyone else have an issue understanding problem D on the mirror sites? The string examples didn't have grids around them. I had to open the original CF problem page.

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3 years ago, hide # |
 
Vote: I like it +16 Vote: I do not like it

In problem E $$$\mathcal{O}((n + m)k^2/\omega)$$$ passes. 213399890. You can uphack if you want.

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3 years ago, hide # |
← Rev. 2  
Vote: I like it +3 Vote: I do not like it

1159 Rank can I reach Expert (1478 >>> 1600)? I am eagerly waiting for the Rating Changes.

Also, why isn't the CF Predictor Extension working lately? Does anyone have an idea about that?

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3 years ago, hide # |
 
Vote: I like it +174 Vote: I do not like it

Very cool problems, thanks!

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    3 years ago, hide # ^ |
     
    Vote: I like it +6 Vote: I do not like it

    How do you lose 267 points in a single contest and still say "very cool problems"?

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      3 years ago, hide # ^ |
       
      Vote: I like it +113 Vote: I do not like it

      The beauty of the problems does not depend on my performance.

      I don't understand the opposite situation when people go to comments after performing poorly and say "It's the worst contest ever". It's not the author's fault that you suck.

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3 years ago, hide # |
← Rev. 2  
Vote: I like it +1 Vote: I do not like it

thank you for this contest!

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3 years ago, hide # |
← Rev. 2  
Vote: I like it +6 Vote: I do not like it

No offense, but did no tester feel that this contest was very unbalanced or that there's no diversity in it? And if they did, why didn't change?

I'm sure high rated people enjoyed the problems, but everyone else got stuck and didn't enjoy as much.

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3 years ago, hide # |
 
Vote: I like it -8 Vote: I do not like it

I think it's the best contest i have joined in my life Back to specialist

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Till now best contest for me. For the first time able to solve A,B,C under 30 mins and also the first time to solve D. Although D was easier comparatively.

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3 years ago, hide # |
 
Vote: I like it +37 Vote: I do not like it

Speedforces ABCD

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

As cyan, i hope to be blue.

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3 years ago, hide # |
 
Vote: I like it -10 Vote: I do not like it

How can one become a tester for a contest??

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    3 years ago, hide # ^ |
     
    Vote: I like it +6 Vote: I do not like it

    Ask authors to participate in testing.

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      3 years ago, hide # ^ |
       
      Vote: I like it +1 Vote: I do not like it

      How can i find the authors before testing?

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        3 years ago, hide # ^ |
         
        Vote: I like it +1 Vote: I do not like it

        There are few coordinators on Codeforces, their names are known. You can occasionally ask them, and they can help you contact authors of upcoming rounds.

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3 years ago, hide # |
← Rev. 3  
Vote: I like it 0 Vote: I do not like it

How to calculate whether i will get a rating increase or decrease

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3 years ago, hide # |
 
Vote: I like it +72 Vote: I do not like it

This contest's problem A is the best a+b problem I've ever seen

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3 years ago, hide # |
 
Vote: I like it +53 Vote: I do not like it

Rating changes?

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3 years ago, hide # |
 
Vote: I like it +24 Vote: I do not like it

Rating changes?

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

What's the maximum number iterations can we run in 1 second? My 213380076 for problem D is O(n * (no of factors of n)) The maximum number of iterations run is around 2.5 * 10 ^ 8. But it takes less than 300 ms. How?

Fact
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3 years ago, hide # |
 
Vote: I like it +29 Vote: I do not like it

When will the rating changes be updated?

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3 years ago, hide # |
← Rev. 2  
Vote: I like it 0 Vote: I do not like it

Anyone, please explain

In problem C why are we taking the maximum of c[i] with 0?

What if we have 1 positive element and the rest as negative?

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    3 years ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    if there is one positive and rest all are negative then you can simply remove all the elements in front of it and back of it , without adding anything

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    3 years ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    Then we can leave only that positive element

    Like -1 -5 6 -8 -> -5 6 -8 -> 6 -8 -> 6

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    3 years ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    you can find the sum of all the positive number on odd indices and same should be done for even

    we are then finding max of them and printing

    in your case when all numbers are negetive suppose -1 -1 -2 5 -9

    we know the ans should be 5

    we know that the sum at odd indices is more now we will choose the number on odd indices that are negetive and remove them -> -3 5 -9 now we will remove -3 and -9

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3 years ago, hide # |
 
Vote: I like it -19 Vote: I do not like it

I have an another solution for D. See Here

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

I am new to code forces, why did this contest not give any rating? I am still having 0.

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

This contest's problem A is the smartest way to learn how to print a+b

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3 years ago, hide # |
 
Vote: I like it +31 Vote: I do not like it

Is it rated?

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3 years ago, hide # |
← Rev. 2  
Vote: I like it 0 Vote: I do not like it

does anyone know how can we predict our rating changes? Becoz CF-Predictor doesn't seem to be working. EDIT: nvm I read the comment above.

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3 years ago, hide # |
 
Vote: I like it +1 Vote: I do not like it

is this contest is unrated??

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3 years ago, hide # |
 
Vote: I like it +5 Vote: I do not like it

Is the round rated...... been waiting for the update since morning

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3 years ago, hide # |
 
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Can someone help me figure out where this code gone wrong for problem C 213370130

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    3 years ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it 
    Input:
1
5
1 -1 -1 -1 1

Your Output:
1

Correct Output:
2

    You can apply the operation twice at the middle element: $$$[1, -1, -1, -1, 1] \rightarrow [1, -2, 1] \rightarrow [2]$$$

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3 years ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

Hope everyone get good scores!

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3 years ago, hide # |
 
Vote: I like it +17 Vote: I do not like it

Is it rated?forces

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3 years ago, hide # |
 
Vote: I like it +16 Vote: I do not like it

ratings updated when??

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3 years ago, hide # |
 
Vote: I like it +11 Vote: I do not like it

I cannot afford to have this contest unrated. Please update ratings.

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3 years ago, hide # |
 
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May I ask what is wrong in writing the question E like this? Can you explain it or give a wrong example? Thank you very much[submission:213474901]

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3 years ago, hide # |
 
Vote: I like it +66 Vote: I do not like it

Ratings updated, sorry for the delay.

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    3 years ago, hide # ^ |
     
    Vote: I like it +2 Vote: I do not like it

    It's okay, buddy, take your time, we don't mind.

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3 years ago, hide # |
 
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thank you for the round! problems are all fun

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3 years ago, hide # |
← Rev. 3  
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Can someone please provide a proof of why for $$$c \gt 0$$$, sorted array works in problem F of this contest? It is pretty unintuitive to me.

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3 years ago, hide # |
← Rev. 2  
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I just received a email stating that one of my submission(D) is significantly similar to some others I received the email for the first time. The code was my own please guide me on how can I prove the code was not copied

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3 years ago, hide # |
 
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Regarding the D problem of this field, this is undoubtedly an excellent topic, just start from 1 to find the factor that the number is not n, and then use n + 1 to go through the structure of abcdef, A, B are brain teaser questions

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3 years ago, hide # |
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I am writing in response to the recent email I received regarding allegations of cheating on my solution for problem B & C. I would like to emphasize that I have never engaged in any form of cheating or misconduct throughout my entire time on Codeforces. I have always approached the platform with utmost integrity and dedication, and I am deeply saddened and shocked by these accusations. I have been an active participant on Codeforces for the past year, consistently solving problems. My commitment to this platform is evident in my profile. I have always strived to improve my programming skills, solve challenging problems, and learn from the talented community on Codeforces. Regarding the specific incident in question, I would like to highlight a few important points. Firstly, the questions in this particular contest were straightforward, and it is possible that multiple individuals arrived at similar solutions independently. Coincidences like these can occur, especially when the problems are relatively straightforward or have limited solution variations. Furthermore, I have always followed ethical guidelines and respected the Codeforces rules. I take pride in the authenticity of my work, and I can assure you that any similarities in code are purely coincidental. I have never resorted to plagiarism or unauthorized use of others' solutions, and I have always strived to solve problems in my own unique way. I kindly request that you thoroughly investigate this matter, considering my track record, my dedication to the platform, and the possibility of coincidental similarities in code solutions. I am confident that a detailed examination will vindicate my innocence. I promise i didnt cheat. MikeMirzayanov

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3 years ago, hide # |
← Rev. 4  
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Is there currently any working site to know deltas after contest ?

https://cf-predictor.wasylf.xyz/ is not working .

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3 years ago, hide # |
 
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Response to cheating in D, Straight of the bat, say like I haven't used any public ide say ideone.com (like the system says_ and other whatever is present since I think it is slow and I am adamant my code runs immediately, and secondly, for this question I have used one code from gfg to find the factors (if n=4, then factors can be 1,2 and 4 (since matrices like 1*4, 2*2, 4*1 can be considered)), and for saving time, took that code from there (link) -> https://www.geeksforgeeks.org/find-all-factors-of-a-natural-number/ (the second post code I have used) (and stored them in set so the factors 2*2 doesn't get inputted twice) and after that I applied own logic and found out the answer. But there was some system check and I have my solution colliding with someother ones. Furthermore, I have always followed ethical guidelines and respected the Codeforces rules. I would like to ask codeforces team to please reply back since it takes lot of practice and time to reach this rating (you can see my graph also, been here for a long time). You can check my previous contest performances and submissions as well and consider my track record. Please reply to me back codeforces team immediately.

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    3 years ago, hide # ^ |
     
    Vote: I like it +1 Vote: I do not like it

    The link you provided is too obvious which may not help you in getting out of this, better give links to your submissions and matching submissions as well and ask for help or consideration.

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3 years ago, hide # |
 
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I was falsely accused of plagiarism. Read this blog Please someone help me out

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3 years ago, hide # |
 
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I recently received a notification regarding problem C, stating that my code bears similarities to the code written by some other participants. I want to clarify that I wrote my code independently, without any external influence. I happened to encounter a similar problem in the past and had already developed an approach to solve it. I believe this is a testament to my dedication and practice in mastering such problem-solving techniques.

I kindly request the Codeforces team to review my situation and provide a response. I genuinely value the effort and time I invest in improving my coding skills, and I hope the team recognizes my commitment to fair competition

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3 years ago, hide # |
← Rev. 3  
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I recently received a notification regarding problem B,C, stating that my code bears similarities to the code written by "VirusARzk" . I want to clarify that I wrote my code independently, without any external influence and i didn't know who is this.

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3 years ago, hide # |
← Rev. 2  
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Dear Codeforces Team, I recently received a plagiarism accusation for problem D during the last contest. I want to clarify that I solved this problem independently and request a rating adjustment accordingly. I assure you that I have always upheld fairness in all my Codeforces submissions. I have reached this rating by giving CF contests continuously and honestly. While my solution may resemble others due to common logic, I affirm that I did not copy anyone's code because of my past experience solving a similar problem elsewhere. I kindly ask you to reevaluate my submission and reconsider the rating adjustment. I value the fair competition Codeforces provides and want to rectify any misunderstandings. Thank you for your attention to this matter. I look forward to your positive response. 213385596 — My submission 213380296 — Person with whom I received plague

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    3 years ago, hide # ^ |
     
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    better provide links to your submission and the submissions which matched yours and then ask for help. It would be clear for them to solve or for any to help you that way.

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3 years ago, hide # |
 
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Why are my last three contest rating changes of -54 -12 +120 gone? I understand a plag check is going on for Round 884, but I don't understand. My rating is the same, but my graph is distorted, and my last three contests are not showing up on the contests page of my profile.

Is this normal or smtg's happening ?

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    3 years ago, hide # ^ |
     
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    Same thing is happening to me. When I put show all it shows the contest and says its unrated.

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    3 years ago, hide # ^ |
     
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    Same thing happened to me, rating for last 3 contests gone as if they're unrated. Also now it says Contest rating: 1301 (max. newbie, 1151), which is strange. I did not recieve any plagiarism letters as some people here. So I dunno what's happening.

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3 years ago, hide # |
 
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Dear Codeforces Team, I wanted to bring to your attention that I recently received a plagiarism notice for problem D of my last contest. However, I want to emphasize that I did not cheat or intentionally copy any code. The similarities in my solution to others might be attributed to the utilization of common logical reasoning and problem-solving approaches. I kindly request you to reevaluate my submission, taking into consideration the possibility that my solution was derived independently. Upholding integrity and fairness is of utmost importance to me, and I have always strived to maintain these principles while participating on the platform.I greatly appreciate the efforts made by the Codeforces team to ensure a plagiarism-free environment. I sincerely believe that the resemblances in code were coincidental rather than a result of deliberate plagiarism.

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3 years ago, hide # |
← Rev. 2  
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I noticed this round got unrated, and wanted to know why so I looked at scores. A bunch of gray people solving problem D. Also other div2 people solving D in under 10 min.

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3 years ago, hide # |
 
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unrated???????????????why??????????

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3 years ago, hide # |
← Rev. 10  
Vote: I like it -18 Vote: I do not like it

.

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3 years ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

Why have the rating changes been revoked?

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3 years ago, hide # |
 
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Roll back？

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3 years ago, hide # |
 
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This is my specialist round so thank you, I really appreciate that.

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