### lavish315's blog

By lavish315, 5 months ago,

We invite you to participate in CodeChef’s Starters 36, this Wednesday, 27th April, rated for Div 2, 3 & 4 Coders.

Time: 8 PM — 11:00 PM IST

Joining us on the problem setting panel are:

Announcing Scholarship for CodeChef Certification in Data Structure & Algorithms — More than 100 Indian participants in Divisions 1, 2, and 3 will win scholarships for the CodeChef Certification exam (discounted prices). Scholarship criteria can be found on the respective contest pages.

The video editorials of the problems will be available on our YouTube channel as soon as the contest ends. Subscribe to get notifications about our new editorials.

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.

Hope to see you participating.

Good Luck!

• +36

 » 5 months ago, # |   +5 As a problem setter, see all the problems and you will regret copying code from gfg.
 » 5 months ago, # |   0 is the CodeChef website slow or it is happening just for me?
•  » » 5 months ago, # ^ |   0 Might have been slow for a couple of minutes when the infrastructure was being ramped up for the contest. But we don't see anything abnormal on our end.
 » 5 months ago, # | ← Rev. 2 →   0 Site's Down for me :( Edt: Now working
 » 5 months ago, # |   0 Is the website really slow for anyone else also?
 » 5 months ago, # | ← Rev. 2 →   0 I'm curious how many people misread Chef will be disappointed if after traveling he does not end up in the capital city. as Chef will be disappointed if he does not end up in the capital city during his travels. instead of Chef will be disappointed if his trip does not end at the capital city.I spent more than 1 hour trying to solve the initial variant before reading samples and realizing I had misread the problem. Took me around 10 mins to get the soln and code it after that T_T.Also is MXPRFT just finding longest common substring? If so why even give this problem, its 2 mins work for someone who knows suffix array (or has a template on hand) and implementation pain of binary search + hashing for the rest of us. I get starters are allowed to have more standard ideas, but in this problem the adhoc part is MUCH easier than the copy paste data structures part....
•  » » 5 months ago, # ^ |   +12 Thanks a lot for your feedback!We are sorry if you found the statement of the problem ROME confusing, but in my opinion, the samples and their explanations were there to completely reject the other interpretation that you got. That being said, we will try our best in future to avoid any minor possibility of such ambiguity. Thank you for pointing it out.For MXPRFT, the problem was intended to be on educational side, to make the participants aware of the existing string data structures that can solve the LCS problem in linear time. Completely agreed that for someone who is aware of these data structures, it was a straightforward problem. But for participants who were not aware of such data structures, I guess having a problem provides a good motivation to go and learn that concept.
•  » » 5 months ago, # ^ |   0 TL was too tight for hashing and Binary search for me
•  » » » 5 months ago, # ^ | ← Rev. 4 →   +3 My Binary Search+Hashing soln took > 4s (while suffix array one took < 0.2s) but some solns with constant factor optimizations aced in the contest.Other AC solns of other testers and setters took atmax 0.4s. Hashing soln is O(Nlog^2N) with O(NlogN) mod operations while Suffix Array/Automata are O(N)/O(NlogN). I believe TL is pretty generous for intended solns.
•  » » » » 5 months ago, # ^ |   +10 Yes I realized hashing isn't intended when I saw people passing on their first attempt ;_;. Guess I will finally learn suffix array now
 » 5 months ago, # |   +15 Code for Suffix tree Longest common substring is wrong given in gfg. have you noticed?