GrandCode：通过智能体强化学习在竞技编程中达到大师级水平
GrandCode: Achieving Grandmaster Level in Competitive Programming via Agentic Reinforcement Learning
Ornith Team, Xiaoya Li, Guoyin Wang, Songqiao Su, Chris Shum, Jiwei Li
AI 速览：GrandCode 是一个面向竞技编程的多智能体强化学习系统，作者报告其在三场 Codeforces 实时比赛中均排名第一，超过所有人类参赛者。
Competitive programming remains one of the last few human strongholds in coding against AI. The best AI system to date still underperforms the best humans competitive programming: the most recent best result, Google's Gemini~3 Deep Think, attained 8th place even not being evaluated under live competition conditions. In this work, we introduce GrandCode, a multi-agent RL system designed for competitive programming. The capability of GrandCode is attributed to two key factors: (1) It orchestrates a variety of agentic modules (hypothesis proposal, solver, test generator, summarization, etc) and jointly improves them through post-training and online test-time RL; (2) We introduce Agentic GRPO specifically designed for multi-stage agent rollouts with delayed rewards and the severe off-policy drift that is prevalent in agentic RL. GrandCode is the first AI system that consistently beats all human participants in live contests of competitive programming: in the most recent three Codeforces live competitions, i.e., Round~1087 (Mar 21, 2026), Round~1088 (Mar 28, 2026), and Round~1089 (Mar 29, 2026), GrandCode placed first in all of them, beating all human participants, including legendary grandmasters. GrandCode shows that AI systems have reached a point where they surpass the strongest human programmers on the most competitive coding tasks.