PC2021: Intermediate results, Problem 2, week 1

By 7th February 2021, there are 951 registered participants from 71 countries (the list of countries is given below). During the first week, 65 solutions were submitted, out of which 44 were correct.

Correct solutions were submitted by:

First Name	Surname	Country	School/University	date	time
Thanadis	Charoenrujijin	Thailand	Suankularb Wittayalai School	31/01/21	13:59
Nikita	Semenin	Russia	Moscow Institute of Physics and Technology	31/01/21	14:29
Manh Quan	Nguyen	Vietnam	Hanoi – Amsterdam High School for the Gifted	31/01/21	14:39
Eddie	Chen	United States	West-Windsor Plainsboro High School North	31/01/21	14:41
Bayram Alp	Şahin	Turkey	Ankara Science HS	31/01/21	14:56
Arhaan	Ahmad	India	Krishna Public School	31/01/21	16:27
Zhening	Li	Canada	Sir John A. Macdonald Secondary School	31/01/21	17:45
Cristiana Andreea	Murgoci	Romania	International Computer Highschool of Bucharest	31/01/21	17:49
Vlad-Ștefan	Oros	Romania	“Grigore Moisil” Informatics High School	31/01/21	18:54
Absur Khan	Siam	Bangladesh	Notre Dame College	31/01/21	20:03
Huiyuan	Wang	China	University of Cambridge	31/01/21	22:48
Pieter	Van Steenweghen	Belgium	Imperial College London	31/01/21	23:18
Vuk	Hip	Serbia	Mathematical grammar school	31/01/21	23:21
Dušan	Beguš	Serbia	Mathematical Grammar School	31/01/21	23:44
Fang Tzu	Hsu	Taiwan	National Taiwan University	01/02/21	01:36
Wesley Antonio	Machado Andrade de Aguiar	Brazil	Military School of Manaus	01/02/21	03:59
Lotus	Chen	China	No.2 High School Shijiazhuang	01/02/21	06:22
Jiaxi	Su	China	NO.1 Middle School attached to Central China Normal University	01/02/21	09:21
Minh	Trang Dao	VietNam	Hus highschool for gifted students	01/02/21	10:07
Yuechen	Zhu	China	Peking University	01/02/21	10:41
Janis	Huns	Latvia	University of Cambridge	01/02/21	11:16
Ameya	Deshmukh	India	St. Joseph’s Convent High School	01/02/21	15:11
Anant	Lunia	India	Delhi Public School RK Puram	01/02/21	21:56
Qian	Lin	China	University of Oxford	01/02/21	22:39
Je Qin	Chooi	Malaysia	Kolej Tuanku Ja’afar	02/02/21	02:43
Jianzheng	Deng	China	Shenzhen Senior High School	02/02/21	02:52
Joshua	Teo	Singapore	NUS High School	02/02/21	08:28
Anastasia	Pozharkova	Russia	MBOU “Gymnasium 91 named after M. V. Lomonosov”	02/02/21	11:36
Xuanyu	Lin	China	Shenzhen Foreign Languages School	02/02/21	14:53
Oliwier	Urbański	Poland	Liceum Ogólnokształcące nr 7 w Poznaniu	03/02/21	12:23
Yu	Lu	China	Suzhou High School of Jiangsu Province	03/02/21	15:12
Batuhan	Keskin	Turkey	Boğazici University	03/02/21	18:03
Sangyul	Lee	Korea	Seoul National University	03/02/21	18:42
Prakhar	Singh	India	IIT Kanpur	04/02/21	07:07
Tevž	Lotrič	Slovenia	University of Oxford	04/02/21	09:27
Gia Hiển	Nguyễn	VietNam	HUS High School for Gifted Students	04/02/21	12:33
Pritesh	Mehta	India	Allen	04/02/21	18:04
József	Gurzó	Hungary	Budapesti Fazekas Mihály Gyakorló Általános Iskola és Gimnázium	04/02/21	19:17
M. Subhi	Abo Rdan	Syria	Knowledge private schools	05/02/21	18:45
Arturo Francisco Ruiz	Mercado	Bolivia	Hno. Felipe Palazón	05/02/21	21:27
Balázs	Kovács	Hungary	Hatvani Bajza József Gimnázium	05/02/21	22:30
Dmitry	Khvatov	Russia	Lyceum “Vorobyovy gory”	06/02/21	18:21
Martin	Vassilev	Bulgaria	SMG “Paisii Hilendarski”	07/02/21	09:52
Deng	Jinqiu	China	Guangdong Experimental High School	06/02/21	10:58

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.