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: www.codechef.com/AUG18

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.

8 Likes

@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 ?
[1]: CodeChef: Practical coding for everyone

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:

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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:

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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);

fflush(stdout);

cin>>a[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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@aryanc403 Do you propose to create MikeMirzayanov page on CodeChef?! XD

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

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

Exactly, waiting for 5 mins here!

@pshishod2646, your complexity analysis is wrong. I will explain it later after the contest.

@likecs - Did you saw my latest solution?

@likecs you might have seen my latest solution (the correct one)… And I am damn clear about my time complexity analysis…I even run my code on my PC for worst case…IT DIDN’T OUTPUT ANYTHING EVEN AFTER 10 MINUTES…

If you want they I can send you my code along with the worst case.

@likecs If the intended solution is same as mine then let me tell you that I know that though time complexity seems O(Something) but it is much less than that…But there is a corner test case for which it is really O(Something) and it time outs!!

@pshishod2645 - I think that its best to discuss this in comments section of the problem, or over mail or a private channel with @likecs , as you both can discuss to your hearts content there :). I also dont want anything like “@pshishod2645 discussed things related to contest but wasnt banned but my friend got banned wtf” since I am actively banning people. Hope you understand my dilemma :slight_smile:

What I can confirm is, that the problem is solvable :slight_smile:

1 Like