Intermediate results for Problem 3 will be available 17:00 GMT, 4/4/21.
By 18th April 2021, there are 1022 registered participants from 71 countries (the list of countries is given below). During the first week, 21 solutions were submitted, out of which 11 had at least one correct part, a or b, see the 0-th hint.
Correct solutions for the part a were submitted by:
| First Name | Surname | Country | School/University | date | time |
| Huiyuan | Wang | China | University of Cambridge | 28/03/2021 | 21:28 |
| Zhening | Li | Canada | Sir John A. Macdonald Secondary School | 29/03/2021 | 04:23 |
| Lotus | Chen | China | No.2 High School Shijiazhuang | 30/03/2021 | 15:56 |
| Antonia | Ghita | Romania | International Computer High School of Bucharest | 01/04/2021 | 14:29 |
| Oliwier | Urbański | Poland | Liceum Ogólnokształcące nr 7 w Poznaniu | 03/04/2021 | 11:52 |
| Joshua | Teo | Singapore | NUS High School | 04/04/2021 | 12:27 |
| Nikita | Semenin | Russia | Moscow Institute of Physics and Technology | 05/04/2021 | 15:55 |
| M. Subhi | Abo Rdan | Syria | Knowledge private schools | 08/04/2021 | 08:56 |
| Caio Augusto | Siqueira da Silva | Brazil | Colégio Objetivo Integrado | 13/04/2021 | 02:16 |
| Vlad-Ștefan | Oros | Romania | “Grigore Moisil” Informatics High School | 13/04/2021 | 16:00 |
Correct solutions for the part b were submitted by:
| First Name | Surname | Country | School/University | date | time |
| Zhening | Li | Canada | Sir John A. Macdonald Secondary School | 29/03/2021 | 04:23 |
| Nikita | Semenin | Russia | Moscow Institute of Physics and Technology | 29/03/2021 | 09:07 |
| Oliwier | Urbański | Poland | Liceum Ogólnokształcące nr 7 w Poznaniu | 29/03/2021 | 12:18 |
| Tevž | Lotrič | Slovenia | University of Oxford | 29/03/2021 | 22:28 |
| Huiyuan | Wang | China | University of Cambridge | 05/04/2021 | 00:23 |
| Vlad-Ștefan | Oros | Romania | “Grigore Moisil” Informatics High School | 13/04/2021 | 16:00 |
Participating countries: Algeria, Azerbaijan, Australia, Bangladesh, Belarus, Belgium, Bosnia and Herzegovina, Bolivia, Brazil, Bulgaria, Cambodia, Canada, China, Croatia, Czechia, Egypt, El Salvador, Estonia, Finland, Georgia, Germany, Greece, Hungary, India, Indonesia, Iran, Israel, Italy, Japan, Kazakhstan, Kenya, Korea, Kyrgyzstan, Latvia, Lebanon, Lithuania, Macedonia, Malaysia, Mexico, Moldova, Mongolia, Nepal, Nigeria, North Macedonia, Pakistan, Peru, Philippines, Poland, Romania, Russia, Saudi Arabia, Serbia, Singapore, Slovakia, Slovenia, South Africa, South Korea, Spain, Sri Lanka, Sweden, Switzerland, Syria, Taiwan, Thailand, Turkey, Turkmenistan, United Arab Emirates, United Kingdom, United States, Uzbekistan, Vietnam.