We invite you to participate in CodeChef’s March Lunchtime, this Saturday, 27th March.
Time: 7:30 PM — 10:00 PM IST. Please note the change in timings. This contest will end at 10 PM instead of the usual 10:30 PM.
The March Lunchtime is going to have Gameskraft, Quadeye Securities, Dialpad, and BetterPlace as the official contest recruiters! Gameskraft is hiring for Javascript and Frontend Developers. Quadeye is on the lookout for brilliant Full Stack Developers in CodeChef’s community. Dialpad is looking to attract top talent from CodeChef for the role of Software Engineer. BetterPlace is looking to hire competent coders from the community for SDE 1 and SDE 2 roles.
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.
Joining us on the problem setting panel are:
Setters: Le Duc Minh, nbmnb, nhdtxdy, Quân Anh
Testers: Shubham TheOneYouWant Anand Jain, Aryan aryanc403 Choudhary, Trùng Mễ, Tran thenymphsofdelphi Xuan Bach, Quang xuanquang1999 Nguyen
Statement Verifier: Jakub Xellos Safin
Editorialist: Nishank IceKnight1093 Suresh
Admin: Jatin jtnydv25 Yadav
Video Editorialists: Chirayu Chirayu Jain, Prachi agarwal19 Agarwal, Darshan darshancool25 Lokhande, Yashodhan ay21 Agnihotri, Bharat Singla, Shivam Bohra, Radoslav radoslav11 Dimitrov, Aryan Agarwala, Meet myth_gemphir Singh Gambhir
Mandarin Translator: Gedi gediiiiiii Zheng
Vietnamese Translator: Team VNOI
Russian Translator: Fedor Mediocrity Korobeinikov
Bengali Translator: Mohammad solaimanope Solaiman
Prizes:
We are doubling the happiness this Lunchtime.
Since it's our birthday month, the Chef is in a generous mood. We shall be giving away prizes to double the number of winners than usual. For example: Instead of Top 10, Top 20 will get the winner laddus. This is applicable across all category winners.
There are also special prizes for women:
- Div 1: top 10 females (300 laddus)
- Div 2: top 6 females (150 laddus)
- Div 3: top 6 females (150 laddus)
The winners can claim cool CodeChef goodies using these laddus. Know more here.
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.
Good Luck!
Hope to see you participating!!
Happy Programming!!
IceKnight1093 looking forward to your editorials!
Announcements27th March, 20:34 IST: Two extra test files have been added to the problem BINARYGA, and all submissions have been rejudged. Sorry for the inconvenience.This happened 5 minutes after I finished the problemset, and I noticed it by pure luck.
Now that I have 600 points again, may I leave the contest, or should I wait for you to challenge my solution one more time?
Adding test data in the middle of a 2.5h contest is not OK.
Sorry about that. There will no further changes to the test data.
Why did the time increase?
Also please don't change contest duration inbetween the contest . It completely ruins the plan ahead and other commitments .
Hello if you didn't notice the unusual high number of AC in the problem LUNCHTIM , then please do. The reason is very weak test cases for 100 pts. O(n^2) solution also passes which was meant to pass for only 30pts. .. The whole contest was a let down in terms of quality of test cases. CodeChef_admin please look into this.
jtnydv25 TheOneYouWant thenymphsofdelphi aryanc403 xuanquang1999 please look into this and update and rejudge the problem to maintain the quality of the testcases in the above mentioned problem statement.
They cant change it now. They should have done it before the contest.
very poor job testers!
But like in Codeforces, some testcases are added during System Testing.. Something like this could be done(and I recommend it to be done for the future contests).. Or just make this contest unrated since there were too many mistakes in this contest by testers
sir, bro i think this round still be rated, as the added test did not affect any div.2 contestants at all. Lunchtim had too generous tests, which is an issue of the team, that should not be so very considerable, and we should forgive that. btw how do you define too many?
LUNCHTIM accepted brute force for a full 100 points rather than partial. It was a very obvious TLE for input array consisting of all same numbers (running in $$$O(n^2)$$$) and yet I guess there was no test file with such cases. All Brute force solutions seem to be passing for full scores. Do correct me if I'm wrong, although if I'm not this contest had some hella messed up test file issues as they added extra test files in the middle of the contest to BINARYGA too...
Ya I too was thinking about that then the high rate of Ac got me curious and I quickly got to submissions list of that problem and to my surprise I didn't saw a TLE verdict so at the end I too submitted a brute and finally came up with AC besides wasting hell lot of time.
Pretty good selection of problems. The average difficulty was OK but the testing phase had some issues. Keep up the good work guys
Now again wait for 30 days to give contest :(
LUNCHTIM had a nice intended solution. Although it could also be done trivially by using segment trees. Over and all, I really liked the problems. Kudos to the authors!
What was the nice Intended solution?
https://discuss.codechef.com/t/lunchtim-editorial/87198
Here is one another tweaked way to solve it with Segment Tree in one pass only ... Segment Tree with coloring/DSU ... My Solution
This lunchtime has a really nice problem set. The first problems are beginner friendly, and the last are very challenging even for an experienced contestant. There are some minor issues though. Adding test files in the middle of the contest was unfortunate, but it ended up absolutely well. The time limit in LUNCHTIM may confuse several people, but overall the problems were great. Good work and best wishes to the setters, testers and all people involved in conducting lunchtime!
Did you mean LUNCHTIM had good test cases? How would you justify a O(N^2) solution passing for 100 points?
You can see this submission ( just checking randomly any passed with N^2 solution ) https://www.codechef.com/viewsolution/44212604
I never said LUNCHTIM had good tests, read my words with caution. I said overall the problems were great (specifically, the ideas and approaches), and never took test cases into account.
apparently there are issues with LUNCHTIM's test cases, but i think the problems were nice.
How much does it usually take for rating calculation in CC contests?
Its updated now