Invitation for August Cook Off, 2018

Hello CodeChef Community!

We’re happy to invite you to the August Cook-Off 2018 sponsored by ShareChat. And there are more reasons to cheer as there are some exciting full-time job opportunities by ShareChat for professionals across the globe. More details can be found on the August Cook-Off contest page.
Looking forward to seeing your participation in the August Cook-Off 2018! This time on the problem setting panel are:

  • Problem Setter: allllekssssa (Aleksa Plavsic)
  • Problem Tester: spiral_out (spiral_out)
  • Editorialist: taran_1407 (taran_1407)
  • Statement Verifier: xellos0 (Jakub Safin)
  • Russian Translator: gomelfk (Fedor Korobeinikov)
  • Mandarin Translator: huzecong (Hu Zecong)
  • Vietnamese Translator: (VNOI Team)

Contest Details:

Time: 19th August 2018 (2130 hrs) to 20th August 2018 (0000 hrs). (Indian Standard Time — +5:30 GMT) — Check your timezone
Contest link:

Registration: You just need to have a CodeChef handle to participate. For all those, who are interested and do not have a CodeChef handle, are requested to register in order to participate.

Prizes: Top 10 performers in Global and Indian category will get CodeChef laddus, with which the winners can claim cool CodeChef goodies. Know more here:

(For those who have not yet got their previous winning, please send an email to

Good Luck!
Hope to see you participating!!
Happy Programming!!


It could be better if timing of contest is from 19:00 to 21:30.

In problem GUZAC. The problem says that pi is not greater than 10^9.
But in actual Sequence pi is greater than 10^9.
I think this is wrong statement.
where pi is the number of candies given to the students.

Editorials for All problems except NQNF have been posted. That one will be posted within one or two days as i am a bit busy, sorry for delay. Hope you find them useful :slight_smile:

Update: Editorial for problem NQNF is also ready, and will appear on discuss once Admin moves it to public. Cheers.


the question guzac was highly miss leading , it was no where mentioned that
pi <=1000000000 only for i<=k

I understand that the statement for GUZAC could be misleading for some people, but the thing is and unless I am wrong, the constraints concern the input of the problem, not the actual solution. So pi <= 10^9 is for the input only.

Hello, as setter of all tasks, I should write something about “wrong” statement of task GUZAC.

First, I am sorry for unclear constraints. I agree it could be described on better way (I didn’t write final version of the texts, anyway I could notice it).

From other side, that constraint wasn’t written in the text of problem- so at least you should ask question if you thought it is for all values. For sure we wouldn’t miss to tell- you must have all elements smaller than 10^9 and write in one line in the end of statement. All queries about this topic were answered in 5-10 minutes.

Thanks for participation, hope to see you in some of next CodeChef contests.

My intuition - this round will be unrated. xD


Why ?? And afaik codeforces Round #505 - 19:05 to 21:05. So you can participate over there.

1 Like

According to me it won’t be better…

don’t make it unrated… xD

nope it says
#for each valid i
so for 0<i<=k it is 0<=p_i<=10^9
but for p_i can be greater than 10^9

it is not mentioned anywhere that 0 < i <= k.
So for 0 < i <= n is also valid.

I disagree. If CF and CC time collides. I will prefer CF.

Intution can be wrong. xD

Author can comment more on what does valid “i” meant…

While what you say is correct about asking the doubt, the panel cannot expect contestant asking doubts for this one. Because after reading the statement, the contestant simply misinterprets what it wanted to convey, and on getting WA he will feel that its a bug in his solution. Its only after they saw the official solution that they found the anomaly.

TLDR: This was not a case of “confusion” because the wrong idea could be very easily taken and hence we cannot expect contestants asking this type of doubt unless highly confident in his solution.

TLDR TLDR: Please read above. XD

1 Like

I agree to @vijju123 completely…
It would be easy to think/ask for this bug and try both solution’s if it was a long challenge
But since it was a short contest people might get confused and they might waste a lot of time in debugging a code which is not incorrect according to their logic only due to some issue with understanding of question…
Some people might get some penalties too…
Though I never saw constraints when I attended the contest… xD