We invite you to participate in CodeChef’s Starters 82, this Wednesday, 22nd March, rated till 6-stars Coders (ie. for users with rating < 2500). This contest is organized by Udyam’23, IIT BHU.
Time: 8:00 PM — 11:00 PM IST
Joining us on the problem setting panel are:
Setters: Shubham shubhamgrg1000 Garg, Ujjwal Krypto_Ray Srivastava, Aniruddh Chimpanzee Patil
Testers: Nishank IceKnight1093 Suresh, Takuki tabr Kurokawa
Statement Verifier: Kanhaiya notsoloud1 Mohan
Video Editorialists: Sundar K Letscode_sundar, Madhav jhamadhav Jha, Suraj jhasuraj01 Jha, Jwala jwalapc , Rohit ezo_tihor Oze
Text Editorialists: Nishank IceKnight1093 Suresh
Contest Admins: Utkarsh Utkarsh.25dec Gupta, Tejas tejas10p Pandey
Written editorials will be available for all on discuss.codechef.com. Pro users can find the editorials directly on the problem pages after the contest.
The video editorials of the problems will be available for all users for 1 day as soon as the contest ends, after which they will be available only to Pro users.
Also, if you have some original and engaging problem ideas, and you’re interested in them being used in CodeChef's contests, you can share them here.
Udyam'23 is the technical fest of the Electronics Engineering Society of IIT BHU, and this contest is conducted under its Competitive Programming and Web Development event, Devbits!!
Link to the Web Development Hackathon organized by Devbits.
So what are you waiting for? Visit our site, register for the event, and get a chance to win cash prizes worth Rs 20k+!!
Hope to see you participating. Good Luck!
Auto comment: topic has been updated by shubhamgrg1000 (previous revision, new revision, compare).
Excited!
How these two pieces are connected together? Is Starters 82 some kind of qualification for the further hackathon or it's two separate things?
These are two separate events, but final winners will be decided on the basis of combined result of both events.
Would recommend participating the round. Problems are good in my opinion. The round might be slightly tougher than usual. It is recommended to read all the problems as some problems are equi-difficult (So pick according to your taste :P)
Orz Krypto_Ray
As a setter, I hope you'll have as much fun solving as we had in preparing :D
Waku waku :)
As a Problem Solver, I like all the problems (Special Treatment for Tree Game)...
Nice Problemset! What is the intended solution for GRIDMEET?
There are a total of N*N significant points where K people can meet. We can fix an x[i] (let's say X) and perform a scanline for all y[j] (let's say Y). After fixing X, points can only be located either low (y<Y) or high (y>=Y). We can start iterating from the smallest Y to the largest. During the scanline, points transition from high to low.
To efficiently track the best K points, we can maintain two sets: one for the high points (s1) and one for the low points (s2). In set s1, we can store the points as {abs(X-x[id])+y[id], id}, and in s2, we can store them as {abs(X-x[id])-y[id], id}. Initially, all points are high, so the best K points are simply the top K elements of s1.
As we move to higher values of Y, some points will shift from s1 to s2, and the iterators tracking the least good points in s1 and s2 can shift a total distance of the number of points shifted. Since the iterators can shift a total distance of N for any X, we can perform this operation in O(NlogN) time. We can iterate over all such values of X in O(NNlogN).