There will be no more hints published. The problem will be kept open for submissions tentatively until 13th February. The next update will be published on 6th February, 13:00 GMT.
By 6th February 2022, 13:00 GMT, there are 1085 participants from 79 countries. 108 solutions to P2 were submitted, out of which 29 were correct.
Correct solutions by university students:
| First name | Surname | Country | School/University | P2 date time DD/MM/YY 00:00:00 |
| Zhening Li | Eddie Chen | Canada/United States | Massachusetts Institute of Technology | 20/12/21 20:52 |
| Deng | Jinqiu | China | Beijing University of Aeronautics and Astronautics | 27/12/21 04:13 |
| Shofar | Sno | Suriname | Anton de Kom University of Suriname | 29/12/21 06:50 |
| Alessandro | Rezzi | Italy | University of Padova | 3/1/22 19:23 |
| Jaroslav | Herman | Czech Republic | Charles University | 5/1/22 15:46 |
| Ameya Vikrama | Singh | India | Indian Institute of Technology Bombay | 9/1/22 20:02 |
| Isaac | Wu | Australia | University of Melbourne | 13/1/22 17:07 |
| Kevin | You | United States | Carnegie Mellon University | 16/1/22 08:20 |
| Yuechen | Zhu | China | Peking University | 16/1/22 14:07 |
| Ziyue | Wang | China | Hebei University of Technology | 16/1/22 16:26 |
| Qian | Lin | China | University of Oxford | 17/1/22 06:08 |
| Felix | Schwarzfischer | Germany | Technical University Munich | 17/1/22 10:49 |
| Ameya | Deshmukh | India | IIT Bombay | 30/1/22 10:53 |
| Yun | Gu | CHINA | Tianjin University | 30/1/22 12:13 |
| Erik | Sünderhauf | Germany | Technical University of Munich | 5/2/22 21:54 |
Correct solutions by pre-university students:
| Vlad-Ștefan | Oros | Romania | “Grigore Moisil” Theoretical High School | 21/12/21 06:22 |
| Luca | Milanese | Italy | Liceo “Leonardo da Vinci”, Terracina | 4/1/22 11:58 |
| Wang | Quanquan | China | Tianjin Yaohua High School | 16/1/22 15:33 |
| Sebastián | Arévalo | El Salvador | Instituto Emiliani | 19/1/22 04:19 |
| Yehyun | Choi | United States | Westlake High School | 22/1/22 23:36 |
| Vuk | Hip | Serbia | Mathematical Grammar School | 23/1/22 12:48 |
| Adam | Džavoronok | Slovakia | Gymnázium Poštová 9 | 23/1/22 14:11 |
| Balázs Csaba | Kovács | Hungary | Hatvani Bajza József Gimnázium | 25/1/22 19:49 |
| Absur Khan | Siam | Bangladesh | Gap Year | 30/1/22 07:53 |
| Sarthak | Panda | India | FIITJEE Bhubaneswar | 31/1/22 08:04 |
| Rhythm | Kedia | India | Lord Buddha Public school | 31/1/22 17:52 |
| Emerson Franzua | Aldana Gavarrete | Honduras | School | 31/1/22 19:47 |
| Alexandar | Roussev | Bulgaria | First Language School | 1/2/22 23:16 |
| Gigi | Tsirekidze | Georgia | LEPL Kutaisi Andria Razmadze physics and mathematical public school N41 | 5/2/22 21:40 |
The list of countries:
Algeria, Argentina, Australia, Azerbaijan, Bangladesh, Belarus, Belgique, Bosnia and Herzegovina, Brazil, Brunei Darussalam, Bulgaria, Canada, China, Costa Rica, Croatia, Czech Republic, Cuba, Egypt, El Salvador, Estonia, Ethiopia, Finland, France, Georgia, Germany, Greece, Honduras, Hong Kong, Hungary, India, Indonesia, Iran, Israel, Italy, Japan, Kazakhstan, Korea, Kosovo, Kyrgyzstan, Latvia, Lebanon, Lithuania, Luxembourg, Macao, Malaysia, Mexico, Moldova, Mongolia, Nepal, Nigeria, North Macedonia, Pakistan, Peru, Philippines, Poland, Romania, Russia, Saudi Arabia, Serbia, Singapore, Slovakia, South Africa, Spain, Sri Lanka, Suriname, Sweden, Switzerland, Syria, Taiwan, Tajikistan, Tanzania, Thailand, Turkey, Turkmenistan, Ukraine, United Kingdom, United States, Uzbekistan, Vietnam