Terms of Use

Your use of the Hong Kong Olympiad in Informatics Online Judge ("Online Judge") is governed by the following terms and conditions. If you disagree with any part of these terms and conditions, you must not use the Online Judge.

The term 'us' or 'we' refers to the Hong Kong Olympiad in Informatics Organizing Committee, which includes members from the Education Bureau, HKSARG, the Hong Kong Association for Computer Education and individuals listed in the past, present and in the future on the About Us page of our official website https://hkoi.org/

Licence Restrictions

Student licence

A student licence allows a Hong Kong day-time secondary school student to use the Online Judge. When the account holder no longer studies at the school, they may only use the account until the 30th of September of the same year.

Full-time Teacher licence

A Full-time Teacher licence allows a full-time teacher who works at a Hong Kong day-time secondary school to use the Online Judge. The teacher shall be reponsible for managing the school's accounts and ensure that they are used in accordance with these terms. When the account holder is no longer a full-time teacher at the school, they must notify us by email and they may only use the account until the 30th of September of the same year.

Instructor licence

An Instructor licence allows a person to use the Online Judge for the purpose of providing instruction to other Licenced Users. Licenced Users include students with assigned Individual Student Licence, and all teachers and students of schools covered by the School Licence (whether or not they are Online Judge account holders). The account must not be used during classes that contain any individual that is not a Licenced User.

Work You Submit

You agree to grant us a Creative Commons Attribution-ShareAlike 4.0 International licence for all works, including but not limited to source codes and files, that you created and submit to the Online Judge. You understand that your work may be shared to the public.

For any work that you submit to the Online Judge that is not created by you, a Creative Commons Attribution-ShareAlike 4.0 International or MIT licence must be obtained from the copyright holder. Attribution must be given as required by the licence.

Copyright and Licence

Unless otherwise specified, we reserve all rights for all contents made available in the Online Judge. For details, please check the licence specified at the bottom of each page.

Privacy and Data

By using the Online Judge, you agree that we can use your data in accordance with our Privacy and Data Policy. Acts of directly or indirectly collect personal data from the Online Judge, such as scraping, is strictly prohibited.

Account and Security

The Online Judge is limited to Hong Kong secondary school students and school admins registered with us. One account is only for one person and one person may only have one account. You agree that you will not share your account to someone else or use someone else's account.


You must not do anything abusive, unlawful, dishonest or malicious. You must respect other users. You agree not to operate your account using any automated tool or any tool other than a browser. We reserve the right of closing your account for any reason, and in such cases, license fees are not refundable.

Hosted Tasks

Your school's subscription may allow you to create Hosted Tasks. Such tasks must be original and created by your school. Your school will retain the full copyright. You agree to, on behalf of your school, grant us a perpetual, worldwide, irrevocable, non-exclusive, royalty-free license to host, use, distribute, sublicense, modify, run, publicly display and create derivative works of the Hosted Tasks materials.

No guarantee on confidentiality

The Hosted Tasks may be accessed by us and other users on the Online Judge. We cannot guarantee that the Online Judge is free from errors that may allow unintended access by other persons.

Warranties and Disclaimers

The Online Judge is provided as-is. We do not guarantee the accuracy, fitness and safety of our contents, and contents contributed by other users. You agree that we will not be responsible for any losses or damages with regard to your use of the Online Judge.