KTH Challenge 2021




In short: You try to individually solve as many problems as possible from a set. This year you are allowed to freely use online resources, see Internet access.


This year KTH Challenge will be held entirely online (on Kattis) because of the ongoing pandemic.

Internet access

You are allowed to freely access the internet with two expections:

  • You are not allowed to take part in any ongoing discussions over the internet during the contest.
  • You may only read information that was published before the start of the contest.

Existing code

You can use any preexisting code found on your computer or on the internet (assuming the code was published before the start of the competition). Any code copied from the internet must include a comment containing a URL to the original source.

The contest

The problem set consists of a number of problems (usually 7-9). The problem set will be in English, and given to the participants when the contest begins. For each of these problems, you are to write a program in any language available on Kattis that reads from standard input (stdin) and writes to standard output (stdout), unless otherwise stated. After you have written a solution, you may submit it using the specified submission system.

The contestant that solves the most problems correctly wins. If two contestants solve the same number of problems, the one with the lowest total time wins. If two top contestants end up with the same number of problems solved and the same total time, then the contestant with the lowest time on a single problem is ranked higher. If two contestants solve the same number of problems, with the same total time, and the same time on all problems, it is a draw. The time for a given problem is the time from the beginning of the contest to the time when the first correct solution was submitted, plus 20 minutes for each incorrect submission of that problem. The total time is the sum of the times for all solved problems, meaning you will not get extra time for a problem you never submit a correct solution to.

Note that the contest is an individual contest, meaning collaboration is not allowed in any form. You are also not allowed to try to harm or damage the contest system.

If you feel that a problem definition is ambiguous, you may submit a clarification request via the submission system. If the judges think there is no ambiguity, you will get a short answer stating this. Otherwise, the judges will write a clarification that will be sent to all contestans.

Last modified: May 01 2021