We invite you to participate in CodeChef’s Starters 207, this Wednesday, 8th October, rated for 5 stars (i.e. for users with rating < 2200).
Time: 8:00 PM — 10:00 PM IST
Joining us on the problem setting panel are:
Contest Admin and Statement Verifier: Shreyan Dominater069 Ray
Tester: Sushil SmolBrain Raaja
Setter: Shreyan Dominater069 Ray, Nishank IceKnight1093 Suresh
Text Editorialist: Nishank IceKnight1093 Suresh
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 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. Hope to see you participating.
Good Luck!








Contest starts in 30 minutes.
Dominater069 can you please post these announcements atleast a day before? instead of posting just few hours before?
Codechef contest are conducted every wednesday , so mostly people remember that
yeah mostly but not always if you see the contest history of past 2 months.
Only 1 day it was Sunday otherwise for the last 1 year I can't recall any day it was not on Wednesday
got it, thanks for letting me know.
Q.4 Balanced subarrays was so easy , however people easily solved Q.5 and Q.6 using gemini as they were formula based questions(maths) and gemini is good at that , this is so annoying like the entire div2 is so biased and hard to escape ,
It feels like it is harder to move from 4 start to 5 star than from 5 star to 6 star
also codechef does not ban people ,
There should be some strict rules against it , some codes i opened even had comments and still was not removed from the database
Can’t you avoid such formula based questions or maybe cross check with the paid version of gemini that was given to free in india
Yeah, it's actually frustrating to see people using AI during live contest!
the distribution of difficulty according to lower divs (div2-4) and div1 submissions is a complete different story . 1500 solved the Subset MEX in div4 and 50 solved in div1 :)
Really Flabbergasted !!
Mass cheating on this and this question. No way people are able to solve these especially under 1-hour in lower divisions. Due to this questions like this are placed so down that most people don't even read them :( please look upon this issue Dominater069
Which questions and how many have you solved today?
First 2 of Div-2, would have solved this only if problem distribution wasn't affected by AI submissions
what was the approach for Q2
Suppose, if the array given is : 1 1 1 3 (i.e. atleast 1-element freq = 1) Then theirs no way possible that one can form such permutation of indices such that (A)pi <= (A)i as, we can't put index-4 (containing largest number) on 4th place, as this would yield us -1, hence we, are only left with position : 1 2 3, which all don't contribute to the answer when '4' is placed under it, but we can place rest all other in correct place... simply sorting (Ai, idx), and assigning ans[idx] = index of previous smaller element... a simple greedy approach.
But, incase we have freq. of all elements > 1, then its always possible to get a score = n.
HOW? suppose we have [group of 1] [group of 2] [group of 3] ... & so on, now we can easily shuffle the indexes within each group, with no condition violation, as it will always hold the equality property i.e.(A)pi = (A)i
HERE's my code : code
Why every other contest is rated till 5 star?? Can't you just increase the frequency of rated till 6 star or rated for all contests?
frequency of cheating happen in cc is increased day by day .
how in the world Subarray ORs is rated 2424? i can't solve it have been trying for an hour!
the statement of this problem says Rᵢ = Lᵢ₋₁ + 1, but according to the test cases it should be Rᵢ = Lᵢ₊₁ − 1