ZCO 2022 Discussion

Hi since I didn’t see a discussion thread for ZCO this year, I decided to make one. Discuss answers/everything else here (I didn’t give ZCO myself though).

Fill your answers on this form - https://forms.gle/FrNSYsH6YcF54cSy5

Remember to stitch your scores when filling the form - Your final score on a problem is the sum of your max scores on each subtask of a problem.

I’ll share the responses soon.

Responses - ZCO 2022 (Responses) - Google Sheets


What will be the cutoff?

200 to be generous.

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Q1 (Vacation) was a pretty clear application of 2D prefix sums, though I wasted some time in the implementation thanks to annoying typos :confused:

Q2 (Messages) really stumped me, I made a brute force-ish solution (with binary encoding to optimize it a little) and got 3 subtasks. I wrote a new solution for the next 2 subtasks, but had no idea for the full solution, ending up with 164 total.

For those of you that got 100 on Q2, any hints?

I would like to request you to please make a column P1+P2.
Please please please.

Really I think 200 is too much. 142 to be sure.

got 49 in class 10,:rofl: though i qualified ZIO

yeah, no way, maybe 130 to 140ish max, though I don’t remember a single ZCO cutoff exceeding 100

yes but will you elaborate binary encoding to optimize it a little.
i m only getting 142

Anyone from Ranchi?

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If you got 142, then I think you passed the first 3 subtasks, which is where I basically converted the binary string of differences between two messages into an integer to handle checking from 0 to 2^N - 1 in a easier way


50 is the max cutoff in zco I think?
I am getting 54.
Was unable to implement prefix sum.

the colours are a nice touch too, thanks!

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Also, did the script for testing test cases locally work properly for everyone? For me, it kept saying WA while the online judge gave me AC

By when is cutoff released?

I’m getting 65, gave it in java.
Did anyone else give it in java?
→ did you AC in Vacation using dp sol?

Anyone knows the cutoff? In 2019 it was 25 will it be the same?

any idea about cutoff for 9th?

is there is any discord server for ioi/inoi? if yes plz give me the link