1. Participation in Náboj Online

Náboj Online is a team competition primarily for high school students. Teams consist of at most five members. There are three categories: Juniors, Seniors and Open. The participants in the Junior category can only be high school students currently not enrolled in the ultimate or penultimate classes (in England the ultimate class is Year 13 or equivalent). The Senior category teams may consist of high school students of any age. Anybody can compete in the Open category.

2. Registration

Schools can enrol for participation on the competition website until the enrolment closing date or reaching the full capacity, whichever comes first. All necessary information on the dates, numbers of registered teams and overall competitor capacity is available on the respective website. The enrolment takes place in two rounds: During the first round, each school may enrol any number of teams, but only the first two teams in each category are accepted into the competition (unless full capacity has been reached), all further teams are put on the waiting list. During the second round, which starts two weeks before the competition, also the third and the fourth enrolled teams for each school in each category are accepted (unless full capacity has been reached). The enrollment ends three days before the competition. If, at that time, full capacity has still not been reached and the waiting list for given competition site is not empty, all remaining teams are accepted so that the fifth enrolled team for each school is accepted, then the sixth one etc., until full capacity is reached or waiting list is empty. Enrolment for the Open category will start during the second round and the capacity of this category will depend on the number of enrolled teams in Junior and Senior categories.

4. The Competition Start

The contestants can participate from anywhere, the only necessary condition is a stable internet connection. The organizers will not be held liable for any damage caused by a poor internet connection on the side of contestants. The members of the team do not have to be together in person during the competition, however, it is recommended for easier communication if they have the option. We ask all contestants to adhere to all health measures effective in their location during the competition. Each registered team will receive two emails: a week and a day before the competition, respectively. The latter one will contain login information necessary to enter the competition interface where the team will be able to access the problems and submit their solutions.

5. Solving the Problems

The Contestants work on any of the six problems they have; the solution is either a single number or multiple numbers. As soon as the team concludes that their result to a problem is correct, they submit it through the competition interface. If the solution is correct, they will be notified and a new problem will unlock. The number of submissions to a given problem is unlimited, however, after submitting an incorrect answer the problem will be blocked and the team will have to wait n minutes (where n is the number of incorrect answers for that problem) to be able to re-submit the solution. That means after submitting an incorrect answer for the first time, the team has to wait one minute, after another incorrect try the team has to wait two minutes, etc.). Submitting an incorrect solution for one problem does not influence other problems. In the last five minutes of the competition, the answers to any problem can be submitted every 10 seconds.

7. The End of the Competition

The competition lasts two hours. After that time has passed, it will no longer be possible to submit any solutions in the competition interface. Immediately after the competition ends and before the results announcement, it will be possible to send any possible complaints to

8. The Winner

In every category wins the local team that solved the highest number of problems. Should several teams solve the same number of problems, the winner is determined on the basis of the highest ordinal number of problems solved. If two or more teams have the number equal, the second highest ordinal number of the problems solved determines the winner etc. In case of teams having the same set of problems solved, the winning order is determined depending on the time of submitting the solutions. If this time is equal, the order is determined depending on the time of submitting the last but one problem etc. The same method is applied to determine the order of the rest of the teams. The same principles are used when determining the national and international results.

9. Permitted Tools

Unlike in the regular competition, it is permitted to use any tools available. However, it is not allowed to receive help from people not participating in the competition. Furthermore, any communication or cooperation between different teams during the competition is strictly forbidden. (The contestants are also forbidden to deliberately destabilize the competition interface).

10. Statute of the Rules

These rules are obligatory for all participating teams regardless of the competition location. By its registration the team confirms that they have read and understood the rules, and that they will comply with them during competition. Failure to comply with the rules may result in disqualifying the team.


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