# Beyond Problem Solving: UOJ-Bench for Evaluating Code Generation, Hacking, and Repair in Competitive Programming

arXiv: https://arxiv.org/abs/2606.12864 · HTML: https://mlsanity.com/paper/2606.12864/

## Key facts

- Cited by 2 papers in the map (data through 14 Oct 2026).
- Builds on 23 of its 28 references that are in the map.
- First posted on arXiv 11 Jun 2026.

## Builds on (most cited first, 23 of 23)

- [Gemini 2.5: Pushing the Frontier with Advanced Reasoning, Multimodality, Long Context, and Next Generation Agentic Capabilities](https://mlsanity.com/paper/2507.06261/) (2025)
- [SWE-bench: Can Language Models Resolve Real-World GitHub Issues?](https://mlsanity.com/paper/2310.06770/) (2023)
- [LiveCodeBench: Holistic and Contamination Free Evaluation of Large Language Models for Code](https://mlsanity.com/paper/2403.07974/) (2024)
- [Competition-Level Code Generation with AlphaCode](https://mlsanity.com/paper/2203.07814/) (2022)
- [TACO: Topics in Algorithmic COde generation dataset](https://mlsanity.com/paper/2312.14852/) (2023)
- [Competitive Programming with Large Reasoning Models](https://mlsanity.com/paper/2502.06807/) (2025)
- [CodeElo: Benchmarking Competition-level Code Generation of LLMs with Human-comparable Elo Ratings](https://mlsanity.com/paper/2501.01257/) (2025)
- [Can Language Models Solve Olympiad Programming?](https://mlsanity.com/paper/2404.10952/) (2024)
- [LiveCodeBench Pro: How Do Olympiad Medalists Judge LLMs in Competitive Programming?](https://mlsanity.com/paper/2506.11928/) (2025)
- [CodeContests+: High-Quality Test Case Generation for Competitive Programming](https://mlsanity.com/paper/2506.05817/) (2025)
- [Large Language Models are Edge-Case Fuzzers: Testing Deep Learning Libraries via FuzzGPT](https://mlsanity.com/paper/2304.02014/) (2023)
- [The RealHumanEval: Evaluating Large Language Models' Abilities to Support Programmers](https://mlsanity.com/paper/2404.02806/) (2024)
- [OJBench: A Competition Level Code Benchmark For Large Language Models](https://mlsanity.com/paper/2506.16395/) (2025)
- [HardTests: Synthesizing High-Quality Test Cases for LLM Coding](https://mlsanity.com/paper/2505.24098/) (2025)
- [ELABORATION: A Comprehensive Benchmark on Human-LLM Competitive Programming](https://mlsanity.com/paper/2505.16667/) (2025)
- [ICPC-Eval: Probing the Frontiers of LLM Reasoning with Competitive Programming Contests](https://mlsanity.com/paper/2506.04894/) (2025)
- [Automated Conformance Testing for JavaScript Engines via Deep Compiler Fuzzing](https://mlsanity.com/paper/2104.07460/) (2021)
- [AetherCode: Evaluating LLMs' Ability to Win In Premier Programming Competitions](https://mlsanity.com/paper/2508.16402/) (2025)
- [AutoCode: LLMs as Problem Setters for Competitive Programming](https://mlsanity.com/paper/2510.12803/) (2025)
- [Can LLMs Generate High-Quality Test Cases for Algorithm Problems? TestCase-Eval: A Systematic Evaluation of Fault Coverage and Exposure](https://mlsanity.com/paper/2506.12278/) (2025)
- [Can LLMs Generate Reliable Test Case Generators? A Study on Competition-Level Programming Problems](https://mlsanity.com/paper/2506.06821/) (2025)
- [Klear-CodeTest: Scalable Test Case Generation for Code Reinforcement Learning](https://mlsanity.com/paper/2508.05710/) (2025)
- [Can Language Models Falsify? Evaluating Algorithmic Reasoning with Counterexample Creation](https://mlsanity.com/paper/2502.19414/) (2025)

## Built on by (most cited first, 2 of 2)

- [Coding Agents as Test-Suite Auditors: Finding What Official Suites Miss While Approaching What They Catch](https://mlsanity.com/paper/2608.01715/) (2026)
- [Beyond the Verdict: Agentic Code Judging with Verifiable Feedback](https://mlsanity.com/paper/2610.18760/) (2026)

## Abstract (arXiv)

Despite strong performance in competitive programming, the role of Large Language Models (LLMs) in supporting human learning in the same setting remains largely unexplored. In this work, we introduce UOJ-Bench, a benchmark designed to evaluate not only the problem-solving ability of LLMs, but also their ability to identify errors in human-written code -- a crucial educational activity traditionally supported by running test cases over online judge systems. UOJ-Bench consists of three distinct tasks: code generation, code hacking, and code repair, all constructed from real-world code submissions on the Universal Online Judge (UOJ) and evaluated through UOJ's native judging infrastructure. Our results show that under one-shot evaluation, even the strongest models fail to identify errors in more than 50% of a set of submissions that have been found to be incorrect by UOJ users. While test-time scaling improves success rates to above 90%, the substantial computational costs incurred from model inference limit its practicality for large-scale deployment. Despite these limitations, we find that the best-performing models under test-time scaling can uncover errors in over 5% of full-score submissions across roughly 30 problems, suggesting that frontier LLMs can already provide complementary signals beyond standard judging systems.
