Invitation to CodeChef August Long Challenge 2018 sponsored by ShareChat!

Hello CodeChef Community!

We are thrilled to invite you to participate in the August Long Challenge 2018 sponsored by ShareChat. In addition, there are some exciting internship and full-time job opportunities by ShareChat for Indian programmers in the August Long Challenge 2018. For more details, you may visit the contest page.
I hope you will join your fellow programmers and enjoy the contest problems. Joining me on the problem setting panel are:

Contest Details:

Time: 3rd August 2018 (1500 hrs) to 13th August 2018 (1500 hrs). (Indian Standard Time — +5:30 GMT) — Check your timezone.

Contest link:

Registration: You just need to have a CodeChef handle to participate. For all those, who are interested and do not have a CodeChef handle, are requested to register in order to participate.


Submissions taking ~6 min to give verdict.

@mgch @likecs, Just want to bring it to your notice, that the test cases for GCDMOD are very weak.

My submission which takes O(10^{12}) operations in the worst case got 100 points. Please look into it.

In problem [INMAT][1], I get this type of verdict of WA (-1.000000) and WA (0.000000) !! What does WA (-1.000000) mean ?

the cordinate compression qs is quite unclear. what does it mean by the subsequence amax(1,i-k)…amin(N,i+k)

I have a doubt in problem INTERACTIVE MATRIX problem statement. Can I ask it here? I asked it in comments sections 3 days ago but no one replied yet :frowning:

1 Like

I liked all these problems, and they’re all easy to understand, even MYST is clear when carefully read. Don’t know why so much question in coordinate compression. But I have problem with that idiot prince. 4 days ago I thought I found the solution and got 10 points with quick coding, and good partially correct answers. Improved it a lot with hundreds of custom tests, fixed little bugs since then but after 4 days later I’m still getting the exactly same result. Now I’m stuck and don’t wanna touch to any other problem… I’m gonna kill that prince myself… or let me try to put a big sign saying “Sorry prince but our princess is on another land” :stuck_out_tongue:

1 Like

i am stuck on coordinate compression. passed all the given test cases expect last sub task (last test case-9).it’s very painful. i couldn’t find anything wrong in my code. checked so many test cases. but nothing happened. can anyone help me with it. :’( :’(

I feel that I’m making mistake in flushing the buffer in INTERACTIVE MATRIX
I’m doing it this way.

printf(“1 %d %d”, i, j);



is it the right way or I am doing something wrong

Is tc 31 something special in Interactive matrix question?

I got all correct except the tc 31… Can it be fault in mu algo or is it just some edge case? Please help all are correct except tc 31

Great problems. This was the first time I competed in Div 1 and it really was educational. Kudos to the setter and tester for making the problems challenging.

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I cannot open . Getting all sort of 500, 504 errors.

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Codechef’s MikeMirzayanov profile page shows Could not find page you requested for. xD


@aryanc403 Do you propose to create MikeMirzayanov page on CodeChef?! XD


I’m assuming there was typo with username of Codechef’s MikeMirzayanov. So, I’m correcting it. If this is not the case then please redo correction. And ban newly linked profile on account of giving false info. xD

@aryanc403 What is this Mike doing here?! :wink:

1 Like

@mgch Translating questions into hindi.

On a (serious)(xD) note on CodeForces (maybe due to existance of real MikeMirzayanov over there). Codechef’s MikeMirzayanov name is not present there .

P.S. - Now I’m waiting to see what will happen now. Will real MikeMirzayanov overturn effect due to non presence of CodeChef’s MikeMirzayanov name over there or not.

Why discuss @Mike when we already got a hardworking @admin tiring herself day and night for you guys to discuss about? :wink:

Codechef’s MikeMirzayanov xD.

Exactly, waiting for 5 mins here!