Olympiads
Author: Benjamin Qi
Major (inter)national olympiads in informatics.
Hello, Which online judge should I practice more to do well in IOI?
oj.uz is a great online judge that has most of the Olympiad problems that you'll probably want to solve. However, other great online judges with different Olympiad problems exist. Also, the OI Checklist is a great way to track your progress.
Here is a list of major (inter)national Olympiads and the online judges where you can solve problems from them. See the IOI members page for additional links.
IOI (International Olympiad in Informatics)
| Resources | ||||
|---|---|---|---|---|
| IOI | topics that can and cannot appear on IOI | |||
- oj.uz
- All problems from 2007-2019 and Reverse from 2003.
- Yandex
- All problems from 2003-2018.
- More lenient time/memory limits.
- DMOJ
- Some problems from 1994-2019.
North America
USACO
- Older Problems
- USACO Training
- Legacy training system
- Does not contain some recent topics (e.g. segment tree)
CCC / CCO (Canada)
- DMOJ
- Most problems from 2000-2020.
Europe
Baltic OI
- CSES
- All problems from 2005-2020.
- Supports virtual contests (great for practice).
- oj.uz
- Most problems from 2011-2020.
CEOI (Central European)
- CSES
- All problems from 2005-2019.
- Supports virtual contests (great for practice).
- oj.uz
- Most problems from 2006-2019.
COI / COCI (Croatian)
Romanian NOI (Romanian)
- Kilonova
- Every national olympiad problem from 2002 onwards.
- Kilonova
- Every Romanian IOI TST problem from early 2000s onwards.
- Kilonova
- Every Romanian EJOI/JBOI junior TST problem from 2008 onwards.
IIOT
- Kilonova
- Most Romanian problems from 2019 onwards.
- olinfo.it
- Most Italian problems from 2016 onwards.
POI (Polish)
- Szkopuł
- All POI problems.
Warning!
Solutions from POI problems are unfortunately only available in Polish.
LMIO (Lithuanian)
- oj.uz
- Most problems from 2017-2019.
Other
Asia
JOI (Japanese)
- oj.uz
- Most problems from 2013-2020.
- Some statements are only available in Japanese.
APIO (Asia-Pacific)
- oj.uz
- Most problems from 2013-2019.
IZhO (Kazakh)
- oj.uz
- All problems from 2011-2014 and 2017-2019.
Other
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