Competitive Programming

Solutions with mini-editorials for many problems, including UVA/SPOJ/IOI/Olympiad problems

OmegaUp is a community-based website for competitive programing training. It's also where Mexican Olympiad in Informatics (OMI : Olimpiada Mexicana de Informática) is hosted.

Google Code Jam is certainly one of the most highly-esteemed programming competitions. The competition consists of unique programming challenges which must be solved in a fixed amount of time. Competitors may use any programming language and development environment to obtain their solutions.

, by Andrey Naumenko (indy256) | CodeLibrary contains a large collection of implementations for algorithms and data structures in Java and C++. You may also visit his GitHub Repository.

, by Takanori MAEHARA (@tmaehara) | High-quality implementations of many hard algorithms and data structures.

, by Simon Lindholm (simonlindholm) et al. | A phenomenally organized, documented and tested team notebook from KTH Royal Institute of Technology. One of the most well-crafted team notebooks (contest libraries) I've ever seen.

Stanford's team notebook is well maintained and the codes within are of high-quality.

, by team RR Watameda (IloveHoang_Yen, flashmt, nguyenhungtam) from National University of Singapore | RR Watameda represented National University of Singapore for the 2016 ACM-ICPC World Finals. The items in this notebook are pretty standard and well-organized.

, by team bcw0x1bd2 (darkhh, bobogei81123, step5) from National Taiwan University | bcw0x1bd2 represented National Taiwan University for the 2016 ACM-ICPC World Finals. This notebook contains robust implementations for advanced data structures and algorithms.

, by foreverbell (foreverbell) | A notebook with some advanced data structures and algorithms including some from the China informatics scene.