Hello Codeforces,
I am happy to invite you to the Final Round of GeeksforGeeks's Code India Code.
We don't want to exclude passionate programmers from enjoying the problem set of the final round. Therefore, the contest will be open for all users but only participants who passed in the Qualification Round held on 6th March will be eligible for the rewards.
Contest Details:
- Finals Link: (Register Here)
- Time: Thursday, 10 March 2022, 7:30 PM to 10:00 PM IST.
- Number of Problems: 7 problems
- There will be no penalties for wrong submissions.
- Tie Breaker: Time to reach X points. (ie, time of last AC solution)
Prizes:
- Rank 1: Macbook Pro + Course voucher worth INR 12,000
- Rank 2: iPad Air + Course voucher worth INR 7,000
- Rank 3: Smart Watch + Course Voucher worth INR 3,000
- Rank 4-25: Tablets + Course Voucher upto INR 1500
- Rank 26-100: Noise Earbuds + Course Voucher upto INR 1500
- Rank 101-200: Noise Smartbands + Course Voucher upto INR 1500
- Additional Reward for top 1000 participants: Free access GeeksforGeeks Premium Plus (Quarterly membership) with which you get: Access to ad-free content, Personal notes, free access to Doubt-Assistance program.
- Prize distribution is limited to those residing in India only.
Problem Setting Panel:
- Contest Coordinators: Ashishgup, AvinashKartik
- Problem Setters: Ashishgup, AvinashKartik, Utkarsh.25dec, bunty_x, i.am.pratik, Omja
- Problem Tester: manpreet.singh, naitikvarshney, jaglike_makkar, vkswhy, aditya_01
Even though the prizes are only for Indians, I would like to invite others to participate — the problem-set contains interesting and challenging problems, with an estimated difficulty of a Div2 — Div1.5 round.
Good luck everyone. See you on the leaderboard!
Can I participate, even I didn't participated in earlier rounds?
Yes.
GeeksforGeeks round 2 was on 10th March.
Coding Ninjas CodeKaze round 2 was on 13th March
Codekaze has more than 10 times participants than GeeksforGeeks Code India Code.
Codekaze has much more prizes than GeeksforGeeks Code India Code.
But despite all this Coding Ninjas declared the result of final round and sent mail. And soon within 1-2 days they will send prizes. On the other hand GeeksForGeeks is doing ....?
And not even replying participants.
Hope this better describes the difference between 2 platforms GFG and Coding Ninjas.
Yeah, really impressed with coding ninjas . From Today onwards , I will Try to participate in Their weekend contests regularly .
Problems of this GFG contest are more interesting than CodeKaze.
where did we find qualification round problem's solutions because those problems are really very challenging awesome and pretty hard also.
here for qualification round problems.
where is solution it is just problems?
here for video analysis, editorial coming soon.
Any idea about which tablets for rank 4-25?
pain killers.
"only participants who passed in the Qualification Round held on 6th March will be eligible for the rewards."
Can This be relaxed?(the qual round was basically solving one <=div2c problem but I missed the contest)Someone who do perform well in finals has skill to clear qualification round anyways
It clearly was not just a div 2 A problem when a CM solves B,C,D and fails to do the A problem. wink
The contest clashes with both Educational Round 124 and Reply Challenge. Is it possible to reschedule the contest?
Yes please, I can only brick so many contests at once
GeeksforGeeks_admin Ashishgup
+1
Any updates on changing the timing? These timings should be discussed before checking all the major websites like codeforces, codechef and atcoder
In Leaderboard, only trusted participants(who solved >=1 problem in qualification round) are present or everyone who took part is present?
Omja ??
Everyone who took part is currently on the leaderboard.
Just a small doubt, Whether prizes will be given according to global rank or rank among the Indian participants?
top X ranks among the Indian participants.
reply from gfg: we only see numbers modulo 982345143764, so there seems to be no problem here.
In the problem Path Function, why are constraints on the number of queries (q) not mentioned?
jtnydv25 T-T
Would someone like to exchange a smartband with me for earbuds?
Me
Plz share your ideas or solution on how you solved or approached the problems. It will be very helpful. Thanks in advance.
Can anyone give some hint for 4th one?
I can tell you about a $$$O(N)$$$ solution.
Firstly let us rewrite the asked value
$$$abs( x*ar[y] - y*ar[x] )$$$ {Now since in problem it is given that ar[i]%i==0 we can substitute ar[x] by $$$k.x$$$(k is a constant) , similarly we will replace ar[y] by $$$d.y$$$ (d is another constant)}
=abs(x*y*d-x*y*k)
= $$$abs(x*y*(d-k))$$$
This shows that for any fixed d and k the best answer will be given by the lowest values of x,y possible.
Now ignoring the above equation for some time, we change our focus. What can be he maximum number of distinct values of $$$ar[i]/i$$$ It is $$$√N$$$.
Using this observation about the maximum number of distinct value we can brute force for all possible pair of values.
Really nice soln. I missed it and ended up overkilling it using convex hull trick. It solves this problem in $$$O(nlogn)$$$ and $$$i$$$ divides $$$a_i$$$ constraint isn't required.
Just one correction regarding time complexity, no of distinct values of $$$ar[i]/i$$$ is $$$O(\sqrt M)$$$ where $$$M=10^6$$$, maximum possible value in the array. For small enough $$$n$$$ we can create a testcase with $$$O(n)$$$ distinct such values, so resulting time complexity would be $$$O(n*\sqrt M)$$$, overall $$$O(N*\sqrt M)$$$, where $$$N=10^5$$$ is sum of values $$$n$$$ across all testcases.
Looking at constraints, it is an intended soln.
Can you explain a little bit how the maximum number of distinct values is sqrt(n)?
So, in total, the maximum number of distinct values would be 2000.
Hey there,
I know they have provided a video solution for the contest but I am stuck on problem D which hasn't been covered in the video solution. Could anyone please give me some hint or approach? Thank you.
D was based on pigeonhole principle.
Rewriting equation
|x*a[y]-y*a[x]|asx*y*|(a[x]/x-a[y]/y)|.In case of n>=2000 answer will be 0.
Since maximum distinct value of ratio, a[i]/i, will be less than 2000 so there must be two index x and y where
a[x]/x=a[y]/yso in that case|x*a[y]-y*a[x]|=x*y*|(a[x]/x-a[y]/y)|= 0. For n<2000 brute force
Can you explain a little bit about how the maximum distinct value of a[i]/i will be less than 2000 always. Did you get this value 2000 by checking for some big test cases,or, is it some intuition based. Please tell me what I am missing.
Thanks
We have a[i] <= 1000000 for all values of i. Now for i >= 1000, we can clearly a[i]/i <= 1000 because of the constraint a[i] <= 1000000. So between the indexes 1000 and 2001 , you have only 1001 distinct values of a[i]/i but there are 1002 indices so some value of a[i]/i has to repeat. So for n>=2001 we can guarantee that the answer is 0. I thing we can reach n>=2000 also using similar line of thought.
Minimize maximum elements can be solved by https://oeis.org/A036990 this series. During the contest, I wrote a brute force solution for n up to 10 and searched that series on OEIS and found the above series, but sadly I wasn't able to finish the code during the contest.
What was the solution for problem Path functions?
Trick 5 and 6 here
Looking at constraints I feel the intended soln is generating all $$$2^{20}$$$ possible basis (using just trick 6) and then doing TRIE+DFS maintaining subtree size for each query.
But its solvable even for $$$w <= 10^{18}$$$ (and easier to code), adamant comment explains how to find kth largest/smallest no using basis.
(Thanks, Utkarsh_Agarwal852 for bumping this comments in recent actions a few weeks ago ;) )
Full submission
you got a good solution ..and i get added as a friend..deal :) ?
You got him a tablet and you're satisfied only by being added as a friend, I wouldn't have settled for anything less than a smartphone at least.
When will the rank winners list be announced?
How to solve the third problem (Two Strings)?
Video editorial is already published : https://youtu.be/Gjj4V-sjeFo
Prize distribution/results when?
GeeksforGeeks round 2 was on 10th March.
Coding Ninjas CodeKaze round 2 was on 13th March
Codekaze has more than 10 times participants than GeeksforGeeks Code India Code.
Codekaze has much more prizes than GeeksforGeeks Code India Code.
But despite all this Coding Ninjas declared the result of final round and sent mail. And soon within 1-2 days they will send prizes. On the other hand GeeksForGeeks is doing ....?
And not even replying participants.
Hope this better describes the difference between 2 platforms GFG and Coding Ninjas.
GeeksforGeeks_admin Ashishgup AvinashKartik Utkarsh.25dec bunty_x i.am.pratik Omja manpreet.singh
Hi! I was the problem setter for this round! If you have any issue with the quality of problems or any problem-related stuff, only then tag me.
And I believe the leaderboard is final; we have removed the cheaters, you can find your rank here.
Will the contestants above rank 200 be included under 200 after removing overseas particpants. Ashishgup Omja
I'm actually quite curious to know how did namangoyal198 managed to cheat his way to the global rank 3 by beating so many ultra-skilled participants. Kudos to GFG team for catching him though.
CONTEXT:
Ranklist before Plag-check
Ranklist after Plag Check
Maybe he was removed from leaderboard because he has not given/qualified round 1.
No, we had removed him for plagiarism. The users who hadn't participated in the Qualification round are still on the leaderboard xD
I doubt that, can you find these non-Indian LGMs on the qualification round ranklist: hitonanode and nirjhorjr ?
Still, a stable newbie beating LGM's is quite fishy anyways (unless he is that mysterious anime character who was waiting for this day to unleash his true potential)
GeeksforGeeks_admin
11 Days passed we haven't got a single mail for conformation of prizes. Although GeeksforGeeks sends spam mails daily to participate in this/that event buy this/that course but when it come for prizes you ghost.
Atleast please reply if it will take some time you should not ghost.
Anyone else got a message to claim your prizes and then a message to ignore the previous email.
I just got the message the claim to claim the prize but nothing of sorts of ignoring the previous mail.
The next message about ignoring the previous mail came at 6:49 pm (IST) to my email address.
Yes I got that too and hence did not bother filling up the form...But then onwards they sent no further mails regarding the prizes...
It's probably because they used a wrong ranklist to give out prizes. I got a somewhat similar mail too, but that was because they earlier told me my rank was 3, but it was 4 instead (so the prize changed).
After they sent the mail asking me to ignore the previous mail, today they sent a mail regarding course voucher. Did you get the mail regarding the prize?
Didn't get the mail for the course voucher either. T.T
I too recieved the 3 month premium free plan and that message asking to ignore the previous mail...But then onwards no further communication has been made from their side regarding the prizes....Seems like they are ghosting us
I solved 2 out of 3 programming questions and didn't even open the quiz part yet I got 3 months premium plus membership for free.
Thanks a lot :)
There was a quiz part?
Is there anyone I can email or contact regarding my prizes?
GeeksforGeeks_admin Ashishgup AvinashKartik
Are you planning to give prizes or not ?
You just ghosted after contest no reply at all.
Learn from other platforms.
You can increase your audience by lots of promotion but you are definitely loosing many because of this trust related issues and you customer support.
Some people have already started receiving prizes. Anyway, I am not associated with the prize distribution or logistics part of it — my job was to admin the contest, so I'm sorry about being unable to help there. I will try to raise the issue and have the GFG Admin reply instead.
They sent a mail on the 21st about the goodies but after 10 mins they sent another mail telling us to ignore it...From then onwards no further communication has been made regarding the prizes...Seems like they ghosted everyone
Did anyone received their prize? I got a mail for filling address details on 31th march but still did not receive my prize. GeeksforGeeks_admin can you please look into it.
Same except that I didn't even get the email.
I got my prize but instead of Noise Earbuds, I received Boat Earbuds.
How??? Where did you fill up your contact details? We did not get any mail informing us to submit our details for getting the prizes
Now after almost 1.5 months I have not received my prize and a single mail about my prize. Atleast pls inform us about the status of the prizes.
They ghosted everyone dude... Idk from where some people got their prizes but 99% of the deserving candidates have not got it till now.. Sets a really bad reputation for gfg.
Same bro. Have almost given up on them.
anyone got their prize?
Yes I did. A couple of weeks back.
Yeah...got a delivery agent suddenly deliver the smartwatch one day without any prior intimidation..