Site Usage Rules – v1

These rules are effective from March 1, 2020.

1. Difficulty Contribution

The difficulty contribution should honestly reflect the difficulty experienced when solving the problem based on the difficulty contribution guidelines. The following types of difficulty contributions may be arbitrarily deleted by the administrators:

a. If a difficulty is assigned to a specific problem that most other users find hard to accept

b. If irrelevant or unhelpful tags are attached to a specific problem

c. If one uses automated scripts to bulk-rate the difficulty of problems they have solved to gain rating points for difficulty contribution

d. If difficulty contributions are made through abnormal methods to gain rating points

e. If the same individual uses multiple accounts to make more than one contribution to a problem

2. Difficulty Contribution Comments

Difficulty contribution comments should be written based on respect for setters, other contributors, and those solving the problems. The administrators can arbitrarily delete the following comments:

a. If they contain hateful content based on race, sex, sexual orientation, region, religion, level of education, or standard of living

b. If they contain derogatory content about the problem setter, other contributors, or those solving the problems

c. If they contain swear words

d. If they write about something unrelated to the problem or solving the problem

3. Source Code Ethics

In the following cases, administrative sanctions may be imposed:

a. Submitting another person's source code as one's own or with modifications to increase rating points

4. Event Participation

The acquisition of rewards may be arbitrarily restricted if the same individual uses multiple accounts to participate in events or similar.

5. Arena

a. You should not discuss the problem with other participants while participating in the arena.

b. You can only participate in the arena with one account per person. However, the following exceptions are allowed:

c. You should not participate in the arena with more than one account simultaneously.

d. It is acceptable for the source code submitted during the arena participation to have been written before the start of the contest, provided that the submitted code does not infringe on the rights of third parties, such as copyright.

e. Participants of a previous contest that includes the same problems, held before or simultaneously, should not participate in the Open Contest arena.

f. If you wish to participate in the arena, you must register up to 5 minutes before the start of the contest.


If a contribution is deleted due to a violation of the above, additional sanctions may be applied depending on the severity of the violation:

Additionally, depending on the administrators' judgment, all contributions made by the violating user may be deleted, or the user's site access may be permanently restricted.