🌟 Wiki of OI / ICPC for everyone. （某大型游戏线上攻略，内含炫酷算术魔法）
Extend your AtCoder
Browser extension which parses competitive programming problems
Makes judging, compiling, and downloading problems for competitive programming easy.
AtCoder command line tools
Competitive Programming Sessions
A graph editor
Push your LeetCode solutions to GitHub in one click. Auto-captures code, builds commit messages with runtime/memory beats, and organizes your coding portfolio.
Codeforces Submit add-on for Competitive Programming Helper
🎵 Official source code and writeups for SekaiCTF 2025!
⚔️ Multiplayer rooms for LeetCode
A gamification-driven platform for problem solvers.
C2Ladders is a reconstruction of old a2oj Ladders with new and updated problemset.
Codeforces Lite is a Chrome extension that enhances Codeforces. It features a built-in code editor with code-saving, language switching, and a timer. The extension also offers an optimized dark theme, custom templates for faster coding, and UI improvements for better navigation.
Get the list of all questions you attempted on a particular date on codeforces, along with your account stats.
AtCoderのパフォーマンス予測を行います
【非公式】 AtCoder 上の問題について、取組み状況を記録していくサイトです。各問題が細かく難易度付けされており、必要な知識を段階的に習得できます。
Online Judge system you can host locally!
A Visual Studio Code Extension for competitive programming.
だれでも競技プログラミングの問題を投稿できるサイトです。
To associate your repository with the competitive-programming topic, visit your repo's landing page and select "manage topics."