As Israeli contestants posted both the APIO 2019 Discussion Thread & the APIO 2020 Discussion Thread, I feel obligated to post this year's discussion thread :D

This year, APIO 2021 is hosted again by Indonesia. For most of the participating countries, APIO 2021 serves as one of the main "TST"s (Team Selection Tests) for IOI 2021 (including Israel). The competition's official website is located Here.

The competition is IOI style, 5 hours long. A maximum of 50 submissions is allowed for each problem. A participant's final score is the sum of the scores the participant got on each problem. A participant's score for a problem is the sum of the scores the participant gained in each subtask of the problem. A participant's score for a subtask is the maximum grade the participant's submissions achieved for that subtask.

APIO Problems are of high quality and are considered good practice for those who wish to participate in IOI.

This thread is intended for discussing results. Furthermore, after APIO 2021 Open Contest ends, this thread shall also be used for discussing the solutions to the problems given in the competition.

Note: Before jonathanirvings writes a comment like this yet again, please note that discussing solutions before APIO 2021 Open Contest ends is prohibited. However, discussing results is allowed.