Important Notice: In order to register for the Team Formation Test, students must attend at least 1 regular training session to become an official Training Team member.

Please visit this page frequently for rule updates.

Date: 13th May, 2023 (Saturday)
Reporting Time: 1:00 – 1:30 p.m.
Reporting Venue: Building entrance of Mong Man-wai Building (facing Festival Walk)
Event Time: 2:00 – 7:00 p.m.
Competition Venue: 2/F, Mong Man-wai Building, City University of Hong Kong
Required Documents: Hong Kong Identity Card (for age verification)
Student ID Card
CityU Guest QR code (for entering CityU campus)

Competition Details and Eligibility

Criteria for participating in the TFT
  • An individual medal winner in HKOI 2022/23.
  • Has an HKOI Online Judge account with the role “HKOI Trainee (2023)”.
  • A full-time Hong Kong secondary school student at all times between 1st Sept 2022 and 1st June 2023.
International Olympiad in Informatics (IOI) National Olympiad in Informatics (NOI) HKOI Training Camp ACM-HK Programming
Contest 2023
Date 28th August – 4th September 2023 22nd – 29th July 2023 30th June – 3rd July 2023 10th June 2023
Location Szeged, Hungary Chengdu, Sichuan The Chinese University of Hong Kong The Chinese University of Hong Kong
Website TBA
Additional Criteria
  • Born on or after 1st July 2003
  • A holder of Hong Kong Permanent Identity Card
  • Born on or after 1st July 2004
  • A holder of Hong Kong Permanent Identity Card
  • Able to read simplified Chinese
  • Born on or before 30th June 2011


Students who do not meet the general criteria but have the role “Non Trainee (2023)” may participate as observers.
Eligible students and observers may register through the judge’s Contests page on or before 2nd May 2023. Walk-in is NOT ALLOWED.

Note: We may reject some or all observers if there is insufficient capacity.

Allowed Programming Languages

The only allowed programming language is C++17.


Each contestant will be assigned a workstation to connect to the competition Virtual Machine via Chrome Remote Desktop. Contestants must not interact with the workstation outside the Virtual Machine.

Virtual Machine


CPU: 4 vCPUs (implemented as 4 hyperthreads on 2 physical cores). Base frequency 2.5 GHz or higher.
Memory: 8 GB or higher
Disk space: At least 2 GB free space on local disk

Personal Keyboards

Contestants are highly recommended to bring one personal keyboard, one mouse and one mousepad for use in the competition. Wireless devices or devices that require installation of drivers, and mechanical keyboards fitted with “blue” switches (or equivalent) are not allowed. The adjudicators reserve the right to examine and disallow any device.

Installed Software

– Operating System: Debian 10 “Buster”
– Display Manager: XFCE4
– Google Chrome
– Software listed in the “Programming Languages” section
– gdb, vim, nano, zip, unzip, cppreference-doc-en-html

Submitted programs will be compiled using the compilers and compilation flags specified in the Help page of the Online Judge. Participants are not allowed to use any of their own resources in the competition.


The paper is only available in English. The paper shall consist of several programming tasks. Each task may carry different points. Each task will be further divided into one or more subtasks. Each subtask may carry different points.

The syllabus consists of the latest version of the IOI syllabus, and all materials covered during this year’s Regular Training sessions.

Submission of Solutions and Adjudication

Contestants should submit their solution source codes to the Online Judge. The judge will compile the source codes submitted by contestants, and then assess the compiled programs by testing them with a set of data unknown to the contestants and a marking scheme to be determined by the Adjudicators. To score points for a subtask, contestants’ programs must be correct for all test cases in that subtask.

Contestants will receive feedback about their submissions, including the type of error first encountered (if any) for each subtask. A contestant’s final score will be the sum of points received from solved or partially-solved subtasks. Contestants may submit at most once per task per 60 seconds, and at most 50 times per task.


During the competition, contestants are allowed to seek clarification on the wordings of the tasks from the Adjudicators by using the competition web interface. Should the condition deem necessary, the clarifications will be announced to all contestants. Clarification related to the solutions will not be entertained.

Any queries about the competition should reach the Chief Adjudicator within 5 minutes after the end of the competition, before leaving the venue. The decision of the Adjudicators will be final.


There is a small chance that the score may change due to change of tests, or indeterminacy of the contestant’s submission. Indeterminacy may arise intentionally due to the use of pseudo-random number generators, or unintentionally due to programming bugs or marginal running time. The Hong Kong Olympiad in Informatics Organizing Committee reserves the right to re-evaluate submissions, and the final score will be that yielded by the final evaluation.


If contestants wish to go to the toilet during the test, they must make a request using the Questions / Announcements feature. Contestants may only go to the toilet upon approval by the invigilators. The invigilators may reject any request that is deemed excessive, or if another contestant is visiting the toilet. It will be regarded as cheating if you leave the seat without the invigilator’s approval.

Selection Algorithm

One ranking for each external competition will be produced. For each competition:

  • – The ranking will only include the students who commit to attend the competition.
  • – Students will be ordered by the total score.
  • – In case of ties, compare their last submission that resulted in a score increase. The one with the earlier submission time shall rank higher.

Then, the potential delegates will be selected as follows:

Step 1: 4 IOI members

The top 4 students in the IOI ranking will be selected.

Step 2a: 1 NOI (Class A) member

The top student in the NOI ranking will be selected.

Step 2b: 1 NOI (Class A) member

The top student in the APIO ranking, including both official and unofficial participants, who score a positive score in TFT will be selected. If we are unable to send unofficial participants to APIO, or if such student is same the one selected in Step 2a, the next student in the NOI ranking will be selected instead.

Step 2c: 2 NOI (Class A) members

The next 2 students in the NOI ranking, excluding the selected IOI members, will be selected.

Step 2d: 1 NOI (Class A) member

The top female student in the NOI ranking who has not been selected so far will be selected.

Step 2e: 3 NOI (Class B) members

The next 3 students in the NOI ranking, excluding the selected IOI members, will be selected.

Step 3: 30 Training Camp members

The top 30 students in the Training Team ranking will be selected. We reserve the right to bypass the TFT process and invite individual students to the Training Camp.

Step 4: 15 ACM-HK Programming Contest members

The IOI and NOI members must attend the contest. Then, top students in the ACM-HK Programming Contest ranking will be selected until there are 15 members (5 teams). Participation is subject to the quota allocated by the organizer and is not guaranteed. The teams will be decided by the HKOI Organizing Committee.

Other Opportunities

Should there be other learning opportunities, the training team may select members with reference to the TFT ranking, APIO results and eligibility criteria.

Required Commitment and Results Announcement

The training team will submit the test results, student profiles, attendance records and comments from the trainers to the Hong Kong Association for Computer Education and the Education Bureau for review and approval. Potential delegates (including backup members) will be requested to sign a Commitment Agreement and Parent’s Consent which must be returned to the Organizing Committee within 5 days in order to be considered further. Except for APIO, withdrawal will not be permitted under any circumstances once the document has been signed.

Potential delegates will be notified of the final selection results. The HKOI Organizing Committee’s decision shall be final.

All selected members are required to attend the Training Camp.