Codestorm prelims

The first coding contest made by me. Codestorm Prelims

Do come and participate. It is on Sunday from 3:00 to 6:00 pm. The problem-set will consist of 7-8 problems. It is a team contest with maximum of 2 members. ACM-style ranking followed. Submissions in all languages supported by Codechef is possible. Winners will get a chance to advance to the Onsite round next week.

The problems are of varying difficulty and from vast number of topics. The problems have been set such that even beginners can attempt a few problems and even the best coders find tough job ahead at the hard ones. I hope you enjoy the contest. The Editorials for the contest will also be put up on Codechef after the Onsite round is over.

Happy Coding :slight_smile:



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Nice problem set. In question Get AC in one go what was logic behind a*b - a - b + 1 if gcd(a,b) == 1 ? I could only get this formula by analyzing pattern…

Also, please move problems to practice section.

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Nice Problem Set…Also , Please release the editorials asap.


Editorials are out with the solutions. Go check them out.

Registrations are open. Do fill the google form link below so that we may contact you for Onsite round if you qualify.

@likecs will these problems be moved to practice section or not??

@vsp4, I have twice sent a mail to Codechef regarding this, one a week ago and second one yesterday, but they have have responded that it will happens in few hours. Actually nothing happened.

And about the Editorials, they will be released on 6/7th March with my solutions too.

The logic was that we want ax+by = n, n+1, n+2, … where x and y are integers or equivalently ax+by=1 should be satisfied for a solution and when such a solution exits, we wanted to find the smallest possible n for which the problem statement holds, which u correctly said is “a*b - a - b + 1”

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Questions have been moved to practice section . You can search them with the code COPR16X when X denotes problem code.


Sorry for the delay.