He is a big big cheater who tries to get away from plagiarism by converting code to python . After his main account 1_2_3_4_5_9 got caught he stopped giving contest from that account and started with 10_11_12. He has now reached Candidate Master in both of his accounts . He has another account by the username 14_15_16.

Both he and amber_100 does cheating together .

Proof :-

1. https://codeforces.net/blog/entry/104525

2. https://codeforces.net/blog/entry/104865

Please MikeMirzayanov take some action against them

Right now there are two long challenges on Codechef each of 3 days but both of them are rated for Div-3.

It would be nice if one of the long challenge is rated for Div-2 as well as there are only 4 rated contests for Div-2 in a month (Lunchtime,Cookoff and 2 STARTERS).

BTW, why there was a drastic increase in the number of participants in yesterday's STARTERS? Normally the number lies around 8-9k but yesterday it was around 15k !!!

CodeChef_admin

Yayy !!!

Problem

Basically you are given an array and you have to keep removing any two unequal elements until the size of the array is minumum.

In the editorial it's said:- We get the following greedy solution — each time we take two characters with maximal occurrences number and delete them.

Can anyone plz tell why this solution always give the optimal answer ? Like why everytime we are selecting the elements with maximum frequency?

Thx a lot !!!

I did not give today's contest today but accidently I looked at the scoreboard and found a lot of submissions for problem A, B, C , D which were much higher than usual.

Hence, I looked online and found that all the solutions for the first 4 problems were leaked.. HERE are the screenshots. I don't want to share the link of the website , it's just for reporting

PROBLEM — D Training Session Solution

PROBLEM — C Delete Two Elements Solution

PROBLEM — B Groups Solution

PROBLEM — A Computer Game

Today, just out of curiosity I saw IBaloff profile, and his rating graph looked something like this

Can anyone explain why his rating graph is looking like this. This is the first time I saw something like this. XDDDD

Hello everyone! This is my code for submission of this problem that occured in today's Div-3 contest

Here the judgement for the case 31 of test-case 2 says:- wrong answer Exceeded limit of person 8 on step 4 (test case 31)

The test case 31 is

10

4 1 0 1 1 1 0 2 1 0

My code is giving the following output:-

5

8 1

8 1

9 1

6 1

4 9

I could not find any error in the answer. Person 8 has 2 sociability .Hence can appear in at-most 2 times.Where is the issue then??

Thanks in advance !!!

Have a nice day :)

In todays September Cook off DIV-2

Here are the some of the people's submission of Adjacency Problem

https://www.codechef.com/viewsolution/51337299

https://www.codechef.com/viewsolution/51337447

https://www.codechef.com/viewsolution/51337114

https://www.codechef.com/viewsolution/51336889

https://www.codechef.com/viewsolution/51297617

https://www.codechef.com/viewsolution/51298173

https://www.codechef.com/viewsolution/51322538

And Many More ...

For the problem Chef and Pairwise Distances

Submission

Submission

Submission

Submission

Submission

Submission

Submission

Submission

Submission(Trying to escape plagiarism by adding dummy code)

Submission(Trying to escape plagiarism by adding dummy code)

Submission

Submission

Any Many more..

For the problem Zebra Crossing :-

Submission

Submission

Submission

Submission

Submission

Submission

Submission

Submission

Submission(Trying to escape plagiarism by using unnecessary #define )

Any Many More...

For the problem, Fake Swaps

just go this link link

All of them have the exact same code !!!!!!!!!

This is the condition for a Div-2 contest. 4 out of 7 problems

Daechwita

I have been trying to sign in to USACO guide since yesterday but it keeps showing this error

Is anyone facing the same issue??

UPD:- Its fixed now. Thanks a lot :)

I already wrote in my previous blogpost here, what would happen in this contest ...

CONTEST LINK

We were given 7 problems(DIV-3)

1. FIND THE DIRECTION

2. The Two Dishes

3. Obtain the Sum

4. The Grid Fill Problem

5. Positive Spewing

6. A Counting Problem

7. ATM Queue

HERE are the solutions that were leaked as already mentioned before

Here are the leaked images(THERE WERE MANY OTHER SOURCES ): —

These are the free ones.. Not including the paid ones

Not just this, people were simply discussing the solutions in the respective groups.

The sixth problem was solved by about 10 people in Div-3 and 40 people in Div-2 . Hence it doesnt have any leaked solutions...

So , for someone who gives the contest seriously HAS to solve the 6th problem so that his/her rank is not affected by this cheating which is really very difficult for any beginner who has started just a few months or even years ago... Hence I seriously dont understand what should we do !!!!!!!!!!!!!!!!!!!!!!!!!!!

What are the point in organizing these contests and investing so much money and resources in organizing them ??????????????????

THIS HAS BEEN HAPPENING FOR THE LAST 1 YEAR AND NO ACTION HAS BEEN TAKEN

Till this it is fine... But this contests has become a buisness for some people.. Some were asking Rs 50(about 0.7$) per problem in Youtube & Telegram per user.. In fact some were even offering CP classes by giving there number etc..

I SERIOUSLY THINK CODECHEF SHOULD STOP CONDUCTING THESE CONTESTS ... BECAUSE MOSTLY PEOPLE(in india especially) HAVE TURNED THIS STARS AND RATING INTO BUISNESS AND SELLING CODES. IT'S A SHAME AND CODECHEF SHOULD BE RESPONSIBLE FOR THIS...!!!!!!!!!!!

UPD:- Since many were saying that this blogpost is an advertisement to share these links for future contests, I blurred the channels name

Hi!

So today there is Codechef starters . I think everyone knows what would happen in the contest.

Some problems would be given . After a few minutes, the solutions would be out on Youtube and Telegram . People will buy/copy from them and submit them… Some will waste their time in finding plagiarism by looking at the submissions and reporting them… No action would be taken by the admin and then another contest will come… This cycle will go on and it is happening for the last 1 year. Hence , I request everyone of you to DONT give todays starters contest. If the submissions are less, then the admin would surely take some action. Simply reporting the submissions is not working. So,

IF YOU SERIOUSLY WANT PLAGIARISM TO STOP, THEN PLEASE DON’T ATTEMPT ANY CODECHEF CONTESTS UNTIL PLAGIARISM CHECKS ARE DONE !!!

Thank you !!!

Hello everyone!!!

I have given a couple of contests on Codeforces till now. I am able to do the first 2 problems in a Div-2 contest , hence get a rank of about 6-7k . I am sure if solve them quickly and don't loose points on wrong submissions , I could reach 4-5k easily. But to get a better rank I need to solve C & D.

Can any please advice or share some tips/tricks about how to solve C & D problems in Div-2 contests? The problem is that on reading the editorial, I find the problems quite easy and I am able to implement them on my own(mostly). But during the contest , I don't get the idea about how should I approach them. Mainly they are of constructive algorithm types but some(D mainly) contains DP & graphs.

Should I simply start solving from the Codeforces problem set by setting the difficulty level 1400-1700 or there is something else that I should do ?

Thanks in advance :)