Hello Codeforces!
I'm glad to welcome all of you to Noobs Round #2(Div. 4). The contest will start at wednesday, January 27, 2021 14:35 UTC. The round will not be rated for any participants since it is unofficial.
Contest link: https://mirror.codeforces.com/gym/102942
You will be given 6 problems and 2 hours to solve them. I recommend you to read all the problems :)
This problem-set were prepared for users with a rating range from 0 to 1400 but anyone is welcome to participate!!
All problems are prepared by me, with a lot of help from the testers and coordinators.
We would like to distribute our thanks equally to the following people who made this round possible.
- Monogon & Ashishgup for excellent co-ordination of the round, and improving several problems and rejecting some bad problems!
- SecondThread for his valuable suggestion.
- doubleux for helping me a lot to improve the problems description.
- smax for helping me to test 'java' and 'python' solution.
- Again SecondThread for helping me to add the contest on 'GYM'.
- Bojack_human for making video tutorial.
- wan-_-s for helping me to improve the problems description.
- alif_cse_ju for helping me to prepare a problem tutorial and solution.
- SecondThread, Ashishgup, Monogon, smax, AST_TheCoder, doubleux, pritishn, wan-_-s, Not-Afraid, steinum, Arpan_Bhowmik, RUDRA_DAS, alif_cse_ju, magic_kiri, Bojack_human, ashkANOn, Aritra741, nirjhorJU, tux, rhssinister1753 for testing the round and roasting providing valuable feedback to the problems. Tester orz!
- And, of course, thank you very much MikeMirzayanov for creating the polygon and codeforces platforms.
- You, for participating!
We hope that statements are short and you will enjoy the problem set!
Good luck to everyone and Have Fun! $$$\;$$$ See you in the round! :)
UPD1: Registration available now!
UPD2: Editorial Published!
UPD3: The round is over smoothly :) I hope you've all enjoyed the round. Congratulations to the winners and to everyone for participating!
Div-4 winners:
Winners from all Participants:
And finally people who were the first to solve each problem:
A. First: Geothermal
Div-4 First : lobotomy
B. First: epsilonr
Div-4 First : epsilonr
C. First: Maksim1744
Div-4 First : lobotomy
D. First: Maksim1744
Div-4 First : epsilonr
E. First: Maksim1744
Div-4 First : googol_S0
F. First: i_love_cuiaoxiang
Div-4 First : HELLO_MF
As a coordinator, I assure you this is not a convoluted scheme to get the top contributor spot back by doing almost nothing.
As the gym poster, I assure you this is definitely a convoluted scheme to post more contests in the gym that I'm not actually the author of.
SecondThread If that's not too big an ask, we'd all love a "Good Morning, Everyone!" gym contest someday.
If the contribution points were displayed to 2 decimal places it would be nice. The table looks the same otherwise almost all the time.
;)
As a tester, I found the problemset to be well balanced and I'm confident that there are some problems that even higher rated participants will enjoy! I recommend everyone to participate.
First of all thanks to everyone involved for making it happen. I really enjoyed the last 2 unofficial Div 4 rounds, so looking forward to this.
But if problems are interesting and vouched for by experienced folks around here, why not make it official?
Can't say for sure as I'm not the co-ordinator, but I guess Codeforces isn't going with the idea of conducting Div. 4 rounds for now.
But I think it's a great for beginners, so I hope more of these unofficial rounds will follow.
Ohh yes! I will try my best to attend.
Hope it's not too rude to rag coordinators Ashishgup and Monogon to know their opinion?
UPD: Everyone downvoting this will lose their rating in next contest that is rated for them.
I am done being polite. No one here deserves that. Everyone is a jerk and just wants to downvote all the time.
So come at me losers! Let the downvote party begin!
ok
As a tester, I found the problem set quite standard for regular contestants. Everyone should participate and enjoy the contest.
As a participant. I would like to thanks to all who put their effort ad time for this. :)
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No sir! It's unrated. Please, check the Second line, it's already bolded.
He is expert
is it rated ?
Yes
No
No.It's unrated.
As a tester i can't participate on such a nice round.
guys do participate to make it more interesting
Why it is not a official rated round??
Because It's not an official Rated round.
But they should make it, second thread and ashishgup coders have contributed in this contest
all the problems are standard and for learning purpose.
Reminder: Just 30 minutes left to start!
Is the handle from which this blog is written also your's?
Just curious as username is quite similar
Yes sir, created for tackle some difficult moment. But attend contest by only one sir.
hmm, you did the latest contest from this account lol.
Thanks for the round! I liked the problems, and F was definitely a bit tricky!
I've uploaded a screencast to my YouTube, which I'll premiere 10 minutes after the end of the contest: https://youtu.be/TXgrIwhC750
(This is my first time trying out the "Premiere" feature, which I believe lets everyone watch & chat live.)
Penalty on testcase 1 :(
Sorry sir! May be it's the rule of 'GYM' contest. :(
As a participant, We need more such rounds from you. Enjoyed solving E :)
Thank you sir. Hope we come back again with more interesting problem :D
Problems are really good and educational. It's great to see many Bangladeshis in the contest arrangement.
Thank you sir!
Out of all the problems E was the only one I had solved earlier and then also I struggled a lot with it.
A was garbage.
Thank you sir for the feedback!
You have made a significant improvement in writing problem statement.Your last round had some unclear problems. This one was quite nice.
Thank you sir :D
Very nice contest, Thank you
welcome sir!
Solutions to all problems: https://youtu.be/bh9KjbjQCrY
thanks for the nice problemset. will only div 4 standing be available ??
No sir. I just find the standing by myself :(
This contest was like div 3, not like div 4.. Noobers have been amazed
Nice problems.Hopeful and excited to see a rated contest from Bangladeshis.
Thank you sir :D May be one day possible a official round from BD.
any one please describe solving process of D please
Let x is a number. To get a smaller number than this we can take binary representation of x and replace some(possibly one) 1 with 0. Now, you are given two number a and b and you have to find two number less than a or less than b.
Take binary representation of both a and b. Now if you find some position where bit of a and b both are 1 then replace any 1 with 0 and you will get the number.
This process will work because when you are performing bitwise xor 1 xor 1 will give you 0 and 1 xor 0 will give you 1. So replacing 1 with 0 will give you larger xor output.
Since you are replacing 1 with 0 so you will get a smaller number which follows the conditions.
All solutions for this contest https://youtu.be/TiZIHyI0Qdg. I loved the problem D most. Nice contest man. I hope this type of contest takes place more often.
hey why cant i open other solution which i havent solved from the leaderboard!?
Thank you sir! I will try and will request secondthread sir to open other submission, if possible.
can you put round #1 link ?
round #1. Not well-prepared sir, but can try. B was garbage tho.
I think the link is wrong, showing
no such contestscan you please check again. may be ok now.
Yes, it's good now, thanks. also please change the settings of solutions, so that we can see other's submission, it will be helpful for all beginners like us. I know editorials are there, but other's solutions can also be helpful :)
i told secondthread sir. Hope he will open, if possible (: