Fangda Guo

Me
   Professor (Assistant), ICT CAS

   ORCID: 0000-0003-2401-6499
   Scopus ID: 56427426700
   ResearchGate: Overview
   WeChat: 476657148
   E-mail: guofangda@ict.ac.cn; gfdyes@gmail.com

Education

Qualification

Research Filed

Publications

You can also see DBLP.

   International Journal

  1. Cohesive Group Nearest Neighbor Queries on Road-Social Networks under Multi-Criteria
    Fangda Guo, Ye Yuan, Guoren Wang, Lei Chen, Xiang Lian, Zimeng Wang.
    IEEE Trans. Knowl. Data Eng. (TKDE), vol. 33, no. 11, pp. 3520-3536, Nov 2021. (CCF-A, JCR-Q1, IF 9.235)
  2. Using reliability risk analysis to prioritize test cases
    Ying Wang, Zhiliang Zhu, Bo Yang, Fangda Guo, Hai Yu.
    Journal of Systems and Software (JSS), vol. 139, pp. 14-31, May 2018. (CCF-B, JCR-Q1, IF 3.514)
  3. Improving the multimodal probabilistic semantic model by ELM classifiers
    Yu Zhang, Ye Yuan, Fangda Guo, Yishu Wang, Guoren Wang.
    Journal of the Franklin Institute, vol. 355, no. 4, pp. 1967-1990, Mar 2018. (JCR-Q1, IF 4.246)
  4. Fast Single Image Super-Resolution via Self-Example Learning and Sparse Representation
    Zhiliang Zhu, Fangda Guo*, Hai Yu, Chen Chen.
    IEEE Trans. Multim. (TMM), vol. 16, no. 8, pp. 2178-2190, Dec 2014. (中科院一区TOP, CCF-B, JCR-Q1, IF 8.182)
  5. Task Allocation in Spatial Crowdsourcing: An Efficient Geographic Partition Framework
    Yan Zhao, Xuanlei Chen, Guanyu Ye, Fangda Guo, Kai Zheng*, Xiaofang Zhou.
    IEEE Trans. Knowl. Data Eng. (TKDE), vol. 36, no. 9, pp. 4943-4955, Sep 2024. (CCF-A, JCR-Q1, IF 9.235)
  6. A Semantic-Consistent Few-Shot Modulation Recognition Framework for IoT Applications
    Jie Su, Peng Sun, Yuting Jiang, Zhenyu Wen*, Fangda Guo*, Yiming Wu, Zhen Hong, Haoran Duan, Yawen Huang, Rajiv Ranjan, Yefeng Zheng.
    IEEE Trans. Neural Networks Learn. Syst. (TNNLS), vol. 36, no. 5, pp. 8100-8111, May 2025. (中科院一区TOP, CCF-B, JCR-Q1, IF 10.4)
  7. Domain Adaptation for Graph Representation Learning: Challenges, Progress, and Prospects [PROJECT] Springer REC.
    Boshen Shi, Yongqing Wang*, Fangda Guo, Bingbing Xu, Huawei Shen, Xueqi Cheng.
    Journal of Computer Science and Technology (JCST), vol. 40, no. 2, pp. 283-300, Mar 2025. (CCF-B)
  8. Dual-Dominated Community Search on Bipartite Graphs [CODE]
    Fangda Guo*, Yanghao Liu, Shiyuan Xu, Jiajun Xu, Haowen Gao, Di Yao, Huawei Shen, Xueqi Cheng.
    IEEE Trans. Services Computing (TSC), under review. (CCF-A, JCR-Q1, IF 5.6)
  9. Finding Prominent Communities in Dynamic Heterogeneous Information Networks
    Yanghao Liu, Fangda Guo*, Yu Guo, Yan Zhao, Huawei Shen, Xueqi Cheng.
    IEEE Trans. Knowl. Data Eng. (TKDE), under review. (CCF-A, JCR-Q1, IF 9.235)

   International Conference

  1. Open3DSearch: Zero-Shot Cross-Modal Retrieval of 3D Models Using Text Queries
    Xiong Li, Yikang Yan, Zhenyu Wen, Qin Yuan, Fangda Guo, Zhen Hong, Ye Yuan.
    ACM Multimedia 2025, under review. (CCF-A)
  2. AutoMixer: Automated Multi-Scale Mixing for Time Series Forecasting Based on Neural Architecture Search [CODE]
    Jiangrong Yang, Haodi Wang, Tangyu Jiang, Yu Guo, Rongfang Bie, Fangda Guo*.
    ACM Multimedia 2025, under review. (CCF-A)
  3. FuzSearch: Towards Efficient Multi-user Encrypted Fuzzy Search for Outsourced Data Privacy-Preserving Management
    Xue Chen, Shiyuan Xu, Fangda Guo*, Jing Wang, Yu Guo, Siu-Ming Yiu.
    34th ACM International Conference on Information and Knowledge Management (CIKM 2025), under review. (CCF-B)
  4. HDKM: A Secure and Efficient Dynamic Key Management Scheme for Edge Computing
    Zhao Bai, Yaran Duan, Nianyun Song, Fangda Guo, Chengjun Cai, Rongfang Bie, Yu Guo.
    34th ACM International Conference on Information and Knowledge Management (CIKM 2025), under review. (CCF-B)
  5. ObfusGuard: Leveraging Indistinguishability Obfuscation for Secure Model Judging
    Nianyun Song, Haodi Wang, Xue Chen, Fangda Guo, Ru Zeng, Yu Guo.
    34th ACM International Conference on Information and Knowledge Management (CIKM 2025), under review. (CCF-B)
  6. zkNAS: Secure and Efficient Outsourced-NAS with Zero-Cost Proxies
    Haodi Wang, Danyang Zhang, Tangyu Jiang, Fangda Guo, Jing Wang, Yu Guo.
    34th ACM International Conference on Information and Knowledge Management (CIKM 2025), under review. (CCF-B)
  7. FPP-HTLC: An Improved Faster and Privacy-Preserving Atomic Swap Protocol
    Zhefeng Sai, Shiyuan Xu, Xue Chen, Mingyue Wang, Fangda Guo*, Yaofei Wang, Rongfang Bie.
    34th ACM International Conference on Information and Knowledge Management (CIKM 2025), under review. (CCF-B)
  8. Binder: Trusted Hardware based Federated Learning against Rollback and Forking Attacks
    Zhao Bai, Mingyue Wang, Yu Guo, Fangda Guo*, Rongfang Bie.
  9. Patch Matter: Fine-grained Radio Signal Pattern Mining via Cross-modality Contrastive Pre-training
    Jie Su, Yuheng Ye, Zhenyu Wen, Fangda Guo, Yejian Zhou, Xiaoqin Zhang.
  10. Toward Privacy-Preserving DualRing Signcryption for IoT Data Sharing Management in Cloud Storage
    Xue Chen, Yu Guo, Haodi Wang, Shiyuan Xu, Fangda Guo*, Xiaohua Jia.
  11. ESC: Edge-attributed Skyline Community Search in Large-scale Bipartite Graphs [CODE]
    Fangda Guo*, Xuanpu Luo, Shiyuan Xu, Haowen Gao, Yanghao Liu, Huawei Shen, Xueqi Cheng.
    European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases (ECMLPKDD 2025), under review. (CCF-B)
  12. BotTrans: A Multi-Source Graph Domain Adaptation Approach for Social Bot Detection
    Boshen Shi, Yongqing Wang, Fangda Guo*, Jiangli Shao, Huawei Shen, Xueqi Cheng.
    European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases (ECMLPKDD 2025), under review. (CCF-B)
  13. Harnessing the Power of Reverse Private Membership Testing for Boosting Unbalanced PSU
    Yuxin Xi, Yu Guo, Shiyuan Xu, Haodi Wang, Yue Zhang, Fangda Guo*, Cong Wang, Xiaohua Jia.
    51st International Conference on Very Large Data Bases (VLDB 2025), under review. (CCF-A)
  14. SecLMM: Towards Secure and Lightweight Inference Service for Large Multimodal Models [CODE]
    Wang Zhang, Yu Guo, Yuxin Xi, Luoxun Liu, Yue Wang, Fangda Guo*.
    IEEE/ACM International Symposium on Quality of Service (IWQoS 2025), accepted. (CCF-B)
  15. Learning Evolving Tools for Large Language Models [CODE]
    Guoxin Chen, Zhong Zhang, Xin Cong, Fangda Guo, Yesai Wu, Yankai Lin, Wenzheng Feng, Yasheng Wang.
    13th International Conference on Learning Representations (ICLR 2025), accepted.
  16. M3GIA: A Cognition Inspired Multilingual and Multimodal General Intelligence Ability Benchmark [CODE]
    Wei Song, Yadong Li, Jianhua Xu, Guowei Wu, Lingfeng Ming, Kexin Yi, Weihua Luo, Yi Du, Fangda Guo, Kaicheng Yu.
    arXiv:2406.05343.
  17. Logarithmic-size Lattice-based Linkable Ring Signature for Cloud Data Management
    Xue Chen, Shiyuan Xu, Fangda Guo*, Yuer Yang, Chunxiao Li, Siu-Ming Yiu.
    30th International Conference on Database Systems for Advanced Applications (DASFAA 2025), accepted. (CCF-B)
  18. Lattice-based Forward Secure Certificateless Encryption Scheme for Cloud Data Management
    Shiyuan Xu, Xue Chen, Yue Wang, Tianrun Xu, Fangda Guo*, Xiaoli Zhang, Siu-Ming Yiu.
    30th International Conference on Database Systems for Advanced Applications (DASFAA 2025), accepted. (CCF-B)
  19. GNN-Based Persistent K-core Community Search in Temporal Graphs
    Zongli Jiang, Yirui Tan, Guoxin Chen, Fangda Guo*, Jinli Zhang, Xiaolu Bai.
    2024 IEEE International Conference on Big Data, pp. 569-578, Washington, USA, Dec 15-18. (CCF-C)
  20. FCS-HGNN: Flexible Multi-type Community Search in Heterogeneous Information Networks [CODE]
    Guoxin Chen, Fangda Guo*, Yongqing Wang, Yanghao Liu, Peiying Yu, Huawei Shen, Xueqi Cheng.
    33rd ACM International Conference on Information and Knowledge Management (CIKM 2024), pp. 207-217, Boise, USA, Oct 21-25. (CCF-B)
  21. Post-Quantum Searchable Encryption Supporting User-Authorization for Outsourced Data Management
    Shiyuan Xu, Yibo Cao, Xue Chen, Yu Guo, Yuer Yang, Fangda Guo*, Siu-Ming Yiu.
    33rd ACM International Conference on Information and Knowledge Management (CIKM 2024), pp. 2702-2711, Boise, USA, Oct 21-25. (CCF-B)
  22. SACH: Significant-attributed Community Search in Heterogeneous Information Networks [CODE]
    Yanghao Liu, Fangda Guo*, Bingbing Xu, Peng Bao, Huawei Shen, Xueqi Cheng.
    40th IEEE International Conference on Data Engineering (ICDE 2024), pp. 3283-3296, Utrecht, Netherlands, May 13-16. (CCF-A)
  23. SecMdp: Towards Privacy-Preserving Multimodal Deep Learning in End-Edge-Cloud [CODE]
    Zhao Bai, Mingyue Wang, Fangda Guo*, Yu Guo, Chengjun Cai, Rongfang Bie, Xiaohua Jia.
    40th IEEE International Conference on Data Engineering (ICDE 2024), pp. 1659-1670, Utrecht, Netherlands, May 13-16. (CCF-A)
  24. Label Noise Correction for Federated Learning: A Secure, Efficient and Reliable Realization
    Haodi Wang, Tangyu Jiang, Yu Guo, Fangda Guo*, Rongfang Bie, Xiaohua Jia.
    40th IEEE International Conference on Data Engineering (ICDE 2024), pp. 3600-3612, Utrecht, Netherlands, May 13-16. (CCF-A)
  25. Deep Dirichlet Process Mixture Model for Non-parametric Trajectory Clustering [CODE]
    Di Yao, Jin Wang, Wenjie Chen, Fangda Guo, Peng Han, Jingping Bi.
    40th IEEE International Conference on Data Engineering (ICDE 2024), pp. 4449-4462, Utrecht, Netherlands, May 13-16. (CCF-A)
  26. M2TA: Enabling Few-Shot Open-Set Incremental Learning via Multi-phase Meta Task Adaptation
    Taotao Li, Jie Su, Zhenyu Wen, Fangda Guo, Yiming Wu, Zhen Hong.
  27. Trajectory Completion via Context-Guided Neural Filtering and Encoding
    Di Yao†, Fangda Guo†, Zhenyu Wen, Yu Guo, Peng Cheng, Yangyuan He, Jingping Bi.
    29th International Conference on Database Systems for Advanced Applications (DASFAA 2024), pp. 3-19, Gifu, Japan, Jul 2-5. (CCF-B)
  28. TimeGAE: A Multivariate Time-Series Generation Method via Graph Auto Encoder
    Zhao Bai†, Fangda Guo†, Zhuoming Zhu, Yuxin Xi, Yu Guo, Rongfang Bie.
    29th International Conference on Database Systems for Advanced Applications (DASFAA 2024), pp. 103-118, Gifu, Japan, Jul 2-5. (CCF-B)
  29. FedDGCL: Federated Graph Neural Network with Dual Graph Contrast Learning for Multivariable Time Series Forecasting
    Ye Zhou, Yu Guo, Fangda Guo*, Fangming Jing, Jiangrong Yang, Rongfang Bie.
    29th International Conference on Database Systems for Advanced Applications (DASFAA 2024), pp. 393-408, Gifu, Japan, Jul 2-5. (CCF-B)
  30. OblivChain: Enabling Oblivious Queries for Blockchain Light Clients with Malicious Security
    Yifang Zhang, Mingyue Wang, Fangda Guo*, Xidi Qu, Yu Guo, Shengling Wang.
    29th International Conference on Database Systems for Advanced Applications (DASFAA 2024), pp. 3-19, Gifu, Japan, Jul 2-5. (CCF-B)
  31. Privacy-Preserving and Efficient Model Aggregation in Edge-Assisted Federated Learning
    Shuyang Wang, Hongcheng Xie, Yu Guo, Fangda Guo*, Fangming Jing, Rongfang Bie.
    29th International Conference on Database Systems for Advanced Applications (DASFAA 2024), pp. 511-521, Gifu, Japan, Jul 2-5. (CCF-B)
  32. Causality and Independence Enhancement for Biased Node Classification [CODE]
    Guoxin Chen, Yongqing Wang, Fangda Guo*, Qinglang Guo, Jiangli Shao, Huawei Shen, Xueqi Cheng.
    32nd ACM International Conference on Information and Knowledge Management (CIKM 2023), pp. 203-212, Birmingham, UK. (CCF-B)
  33. TOAK: A Topology-oriented Attack Strategy for Degrading User Identity Linkage in Cross-network Learning [CODE]
    Jiangli Shao, Yongqing Wang, Fangda Guo*, Boshen Shi, Huawei Shen, Xueqi Cheng.
    32nd ACM International Conference on Information and Knowledge Management (CIKM 2023), pp. 2208-2218, Birmingham, UK. (CCF-B)
  34. CANA: Causal-enhanced Social Network Alignment [CODE]
    Jiangli Shao, Yongqing Wang, Fangda Guo*, Boshen Shi, Huawei Shen, Xueqi Cheng.
    32nd ACM International Conference on Information and Knowledge Management (CIKM 2023), pp. 2219-2228, Birmingham, UK. (CCF-B)
  35. Improving Graph Domain Adaptation with Network Hierarchy [CODE]
    Boshen Shi, Yongqing Wang, Fangda Guo*, Jiangli Shao, Huawei Shen, Xueqi Cheng.
    32nd ACM International Conference on Information and Knowledge Management (CIKM 2023), pp. 2249-2258, Birmingham, UK. (CCF-B)
  36. Towards Dynamic and Reliable Private Key Management for Hierarchical Access Structure in Decentralized Storage
    Yifang Zhang, Mingyue Wang, Yu Guo, Fangda Guo*.
    32nd ACM International Conference on Information and Knowledge Management (CIKM 2023), pp. 3371-3380, Birmingham, UK. (CCF-B)
  37. Cross-Scenario Maneuver Decision with Adaptive Perception for Autonomous Driving
    Yuan Fu, Shuncheng Liu, Yuyang Xia, Fangda Guo, Kai Zheng.
    32nd ACM International Conference on Information and Knowledge Management (CIKM 2023), pp. 535-544, Birmingham, UK. (CCF-B)
  38. Batch-Mix Negative Sampling for Learning Recommendation Retrievers [CODE]
    Yongfu Fan, Jin Chen, Yongquan Jiang, Defu Lian, Fangda Guo, Kai Zheng.
    32nd ACM International Conference on Information and Knowledge Management (CIKM 2023), pp. 494-503, Birmingham, UK. (CCF-B)
  39. OpenGDA: Graph Domain Adaptation Benchmark for Cross-network Learning [CODE]
    Boshen Shi, Yongqing Wang, Fangda Guo*, Jiangli Shao, Huawei Shen, Xueqi Cheng.
    32nd ACM International Conference on Information and Knowledge Management (CIKM 2023), pp. 5396-5400, Birmingham, UK. (CCF-B)
  40. DCGNN: Dual-Channel Graph Neural Network for Social Bot Detection [CODE]
    Nuoyan Lyu, Bingbing Xu, Fangda Guo*, Huawei Shen.
    32nd ACM International Conference on Information and Knowledge Management (CIKM 2023), pp. 4155-4159, Birmingham, UK. (CCF-B)
  41. Multi-attributed Community Search in Road-social Networks [CODE]
    Fangda Guo, Ye Yuan, Guoren Wang, Xiangguo Zhao, Hao Sun.
    37th IEEE International Conference on Data Engineering (ICDE 2021), pp. 109-120, Chania, Greece, Apr 19-22. (CCF-A)
  42. Cohesive Group Nearest Neighbor Queries Over Road-Social Networks
    Fangda Guo, Ye Yuan, Guoren Wang, Lei Chen, Xiang Lian, Zimeng Wang.
    35th IEEE International Conference on Data Engineering (ICDE 2019), pp. 434-445, Macau, China, Apr 8-11. (CCF-A)
  43. A data Processing Method for Fault Prediction of Industrial Pipeline Time Series Data
    Bo Yu, Fulong Xu, Fangda Guo, Sai Gao.
    4th IEEE International Conference on Computer and Communications (ICCC 2018), pp. 1779-1784, Chengdu, China, Dec 7-10.
  44. Compressive Sensing with Measurement Matrix Constructed by Cat Map
    Yanjie Song, Wei Zhang, Fangda Guo, Hai Yu, Zhiliang Zhu.
    International Symposium on Nonlinear Theory and its Applications (NOLTA 2014), pp. 389-392, Luzern, Switzerland, Sep 14-18.
  45. Gabor-Filtering-Based Completed Local Binary Patterns for Land-Use Scene Classification
    Chen Chen, Libing Zhou, Jianzhong Guo, Wei Li, Hongjun Su, Fangda Guo.
    IEEE International Conference on Multimedia Big Data (BigMM 2015), pp 324-329, Beijing, China, Apr 20-22.

   Chinese Journal

  1. Relation Classification Based on Multi-Head Attention and Bidirectional Long Short-Term Memory Networks
    Feng Liu, Sai Gao, Bihui Yu, Fangda Guo.
    Computer Systems & Applications, vol. 28, no. 6, pp. 118-124, Jun 2019. (CCF-C)
  2. IoT Application Service Platform Based on Message Middleware and MongoDB
    Feng Liu, Zhaopeng Wang, Bo Yu, Fangda Guo.
    Computer Systems & Applications, vol. 28, no. 5, pp. 90-94, May 2019. (CCF-C)
  3. Time Optimal Trajectory Planning Algorithm for Industrial Robots with Improved Particle Swarm Optimization
    Yubao Wang, Shiyu Wang, Beibei Li, Fangda Guo.
    Journal of Chinese Computer Systems, vol. 39, no. 8, pp. 1878-1881, Aug 2018. (CCF-B)

Patents

  1. 红外式多点交互电子白板系统及白板投影标定方法
    Tao Ren, Zheng Fang, Xia Li, Fangda Guo.
    Patent NO.: ZL201210376112.8
  2. 一种基于多维属性得分的 top-j 社区搜索方法及装置
    Hao Sun, Ye Yuan, Fangda Guo.
    Patent NO.: CN113221022A
  3. 红外式多点交互电子白板系统
    Software Copyright
    Register NO.: 2013SR069763

Projects

  1. 大规模属性异质图的社区发现研究，国家自然科学基金青年科学基金项目，2024.1-2026.12，30万，主持
  2. 多层信息网络的社区发现研究，中国科学院特别研究助理资助项目，2021.11-2023.11，80万，主持 <300/年
  3. 网络空间群体认知测绘关键技术及应用，中国科学院GF科技创新专项重点部署项目，2024.9-2026.9，300万，主持 青年人才
  4. 面向大规模时序图的社区发现研究，中国博士后科学基金面上资助，2022.6-2024.6，8万，主持
  5. 数字人形象展示技术，科技委，2022.6-2023.12，500万，执行负责
  6. 认知系统的表征建模与调控机理研究，战略先导计划，2023.11-2024.10，39万，执行负责
  7. 可计算文化大模型构建技术，科技委，2023.5-2024.12，1000万，骨干
  8. 面向特定舆论场的认知理解关键技术研究，国家重点研发计划课题，2022.8-2024.7，593万，骨干
  9. 面向非集风险主体的隐性知识建模与分析方法研究，国家重点研发计划（子课题），80万，骨干
  10. 面向特定场景的社会域建模技术，科技委，2022.4-2023.12，240万，骨干
  11. 认知博弈的交互模拟，中国科学院先导专项，2023.12-2028.11，1163.98万，骨干
  12. 内容分析系统，国家计算机网络与信息安全管理中心，2022.6-2024.6，1175万，参与
  13. 大图数据管理与分析的基础理论与关键技术研究，国家自然科学基金重点项目，参与
  14. 应用驱动的大图数据建模理论与算法研究，国家自然科学基金重点项目，参与
  15. 面向社会计算的众包数据管理与分析技术研究，国家自然科学基金海外及港澳学者合作研究基金，参与
  16. 批流融合大数据计算系统，国家重点研发计划课题，参与
  17. 基于动态异构图语义分析的知识图谱存储和检索关键技术研究，国家重点研发计划课题，参与

Honors

  1. 省优博推荐、优秀博士学位论文、优秀硕士学位论文
  2. 优秀科研人员、“新百星计划”
  3. 国家留学基金资助、意大利全奖
  4. 全国大学生创新实验计划国家级优秀
  5. 全国挑战杯省级特等奖、全国创业计划竞赛省级一等奖
  6. 百万青年创业计划全国总决赛三十强
  7. Android应用开发挑战赛国家级优秀奖
  8. 华为奖学金、优秀研究生奖学金、优秀学生奖学金
  9. 年级会主席、基础学院交流部部长、三好研究生、优秀学生干部/标兵、优秀毕业生干部

Talks

  1. ICDE 2024 — Graphs, Networks, and Semistructured Data XV, May 2024
  2. 中国人工智能学会（CAAI）— 全国智能技术与服务学术论坛，June 2019
  3. ICDE 2019 — Graph Data Management 1, April 2019
  4. ICDE 2021 — Graphs 3: Social Networks, April 2021
  5. 讲座报告：中国科学院计算所、北京理工大学、爱丁堡大学、西北工业大学、帕维亚大学等

Peer review & Memberships

  1. 科技委专办主任、重任局业务主管
  2. PC Member: CIKM 2022, AAAI 2023, ICDE 2023 Industry, CIKM 2023, IEEE DSC 2023, CIKM 2024, BigData 2024, MSN 2024, KDD 2025, CIKM 2025, WWW 2025, ACMMM 2025 etc.
  3. (External) Reviewer: TKDE, VLDBJ, WWW Journal, SIGMOD, PVLDB, ICDE, KDD, SIGIR, ESWA, Frontiers of Computer Science, Journal of Data and Information Quality, etc.
  4. IEEE Member, 中国计算机学会, 中国人工智能学会, 中国中文信息学会

Student Guidance

  1. Ph.D.: Yanghao Liu, Boshen Shi, Jiangli Shao (UCAS); Shiyuan Xu (HKU)
  2. Masters: Xuanpu Luo, Cheng Yu, Guoxin Chen, Haowen Gao (UCAS); Nuoyan Lyu (BUPT); Jiutai Jia (BJTU); Yirui Tan (BJUT); Zimeng Wang, Hao Sun, Siqi Sun (NEU)
  3. Undergraduates: Jiajun Xu (BNU); Jinlei Chen, Yuhan Liu (NEU)
  4. #Provincial Talent Plan students: 2


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