arXiv subjects

Minnan Wei

Publications and source records attributed to Minnan Wei.

3 recordsLinked to original sources

arXiv2026

ARIADNE: Agentic Reward-Informed Adaptive Decision Exploration via Blackboard-Driven MCTS for Competitive Program Generation

Competitive program generation aims to automatically produce correct and efficient solutions for programming-contest problems under strict time and memory constraints. Existing LLM-based approaches often fail to perform explicit algorithmic planning and to handle edge cases robustly, leading to unreliable one-shot generation. Moreover, although execution feedback is essential for iterative debugging and refinement, incorporating such feedback effectively within limited computational budgets remains difficult. To overcome these limitations, we propose {\tool}, a blackboard-driven Monte Carlo Tree Search (MCTS) framework that models program generation as a sequential decision process. {\tool} organizes the generation workflow into five coordinated stages (i.e., strategy selection, code generation, test generation, quality evaluation, and code repair) while maintaining a shared blackboard that accumulates structured evidence to guide subsequent decisions. Experiments on four benchmarks (APPS, CodeContests, CodeContests+, and LiveCodeBench) show that {\tool} consistently achieves the best Pass@1 performance across multiple LLM backends. With GPT-4o, {\tool} attains Pass@1 scores of 41.30, 46.67, 27.27, and 20.91, surpassing the strongest baseline CodeSim by up to 26.06 points, while further improvements are observed with DeepSeek-V3.2. These results indicate that combining global search through MCTS with persistent evidence accumulation on a shared blackboard enables systematic exploration and effective feedback utilization, substantially enhancing the capability of LLMs in competitive program generation.

cs.SE↗

arXiv2025

Improving vulnerability type prediction and line-level detection via adversarial training-based data augmentation and multi-task learning

Context: Software vulnerabilities pose a significant threat to modern software systems, as evidenced by the growing number of reported vulnerabilities and cyberattacks. These escalating trends underscore the urgent need for effective approaches that can automatically detect and understand software vulnerabilities. Objective: However, the scarcity of labeled samples and the class imbalance issue in vulnerability datasets present significant challenges for both Vulnerability Type Prediction (VTP) and Line-level Vulnerability Detection (LVD), especially for rare yet critical vulnerability types. Moreover, most existing studies treat VTP and LVD as independent tasks, overlooking their inherent correlation, which limits the potential to leverage shared semantic patterns across tasks. Methods: To address these limitations, we propose a unified approach that integrates Embedding-Layer Driven Adversarial Training (EDAT) with Multi-task Learning (MTL). Specifically, EDAT enhances model robustness by introducing adversarial perturbations to identifier embeddings, guided by semantic importance. Meanwhile, MTL improves overall performance by leveraging shared representations and inter-task correlations between VTP and LVD. Results: Extensive experiments demonstrate that our proposed approach outperforms state-of-the-art baselines on both VTP and LVD tasks. For VTP, it yields notable improvements in accuracy, precision, recall, and F1-score, particularly in identifying rare vulnerability types. Similarly, for LVD, our approach enhances line-level detection accuracy while significantly reducing false positives. Conclusion: Our study demonstrates that combining EDAT with MTL provides a unified solution that improves performance on both tasks and warrants further investigation.

cs.SE↗

arXiv2025

Evaluating and Improving Large Language Models for Competitive Program Generation

Context: Due to the demand for strong algorithmic reasoning, complex logic implementation, and strict adherence to input/output formats and resource constraints, competitive programming generation by large language models (LLMs) is considered the most challenging problem in current LLM-based code generation. However, previous studies often evaluate LLMs using simple prompts and benchmark datasets prone to data leakage. Moreover, prior work has limited consideration of the diversity in algorithm types and difficulty levels. Objective: In this study, we aim to evaluate and improve LLMs in solving real-world competitive programming problems. Methods: We initially collect 117 problems from nine regional ICPC/CCPC contests held in 2024 and design four filtering criteria to construct a curated benchmark consisting of 80 problems. Leveraging DeepSeek-R1 as the LLM, we evaluate its competitive program generation capabilities through the online judge (OJ) platforms, guided by a carefully designed basic prompt. For incorrect submissions, we construct a fine-grained error taxonomy and then propose a targeted improvement framework by combining a multi-turn dialogue-based repair phase and an information-augmented regeneration phase. Results: Experimental results show that only 5 out of 80 problems are fully accepted when using basic prompts. For the unsolved problems, we construct the error taxonomy, including general errors (such as design, boundary, condition, data type, syntax, and input/output errors) and specialized errors (such as those in mathematical problems, greedy algorithms, and graph theories). After applying our proposed improvement strategies, we substantially increased the number of correct solutions, with 46 out of 80 problems successfully accepted.

cs.SI↗