1. The registration should be done by the contestant.
  2. The registration period is 00:00 23rd June to 23:59 29th June 2020. Contestants who do not register by the deadline shall forfeit their eligibility.
  3. There are no consequences if the contestant does not attend the competition (HKOI / TFT / APIO) after registration.
  4. The venue assignment will be announced on 6th July, 2020.


Contestants should log into HKOI Online Judge using their existing account / the finalist practice account provided to them through their schools. Information about the accounts, titled “[Join HKOI] Hong Kong Olympiad in Informatics 2019/20”, have been emailed to the contact persons listed in the HKOI Nomination Form on 20th November 2019. If the email or password is lost, a contact person must contact the Organizing Committee by email at on or before 27th June 2020 to obtain the account information.

Enter HKOI Online Judge Contests page

Please refer to the presentation for step-by-step instructions: (Google Slides / PDF Version)

Competition Venue Assignment

The main purpose of using two competition venues is to facilitate social distancing to reduce the risk of disease transmission. Contestants’ preference, capacity utilization and travel time will be taken into account when allocating competition venue.
Note: The organizing committee reserves the right to override any venue assignment.

Target utilization

The capacities of the two competition venues are as follows: (Subject to change if machines are found inoperative or for other reasons)
Yan Oi Tong Tin Ka Ping Secondary School: C1 = 40 (2 computer rooms)
Pui Ching Middle School: C2 = 48 (3 computer rooms)

Assume that at the end of the registration period, N contestants in a particular group registered for the Final Event, then the target utilization shall be U = N / (C1 + C2). The target number of contestants Tv for a competition venue v would be its capacity Cv multiplied by U. Denote Pv be the number of contestants who prefer the competition venue v. If Pv > T then T would be rounded up. Otherwise T would be rounded down.

Contestants’ Preference

For those contestants who prefer the venue which has PvTv, they will all be assigned to the venue v.

For those contestants who prefer the other venue, they will be assigned to either venue based on their travel time score delta.

Travel Time Score

We use the address of their school to approximate a contestant’s location. The transit duration from the contestant’s school to the two competition venues (Arrive by 08:30 on 18th July, 2020) is obtained using Google Maps API. If the transit duration is Dv seconds, then the travel time score Sv = e(Dv/3600). The travel time score delta is the score for Yan Oi Tong Tin Ka Ping Secondary School minus the score for Pui Ching Middle School.

For example, in case PvTv for Yan Oi Tong Tin Ka Ping Secondary School, then among the contestants who prefer Pui Ching Middle School, the (TvPv) contestants with the least score deltas will be assigned to Yan Oi Tong Tin Ka Ping Secondary School. Tie-breaker for contestants having the same delta (same school): The contestants who rank higher in the nomination form will get their preferred venue.

See all Travel Time Score Deltas