Journal of Computer Science and Technology

, Volume 16, Issue 4, pp 388–391 | Cite as

Hardness and methods to solve CLIQUE



The paper briefly reviews NP-hard optimization problems and their inapproximability. The hardness of solving CLIQUE problem is specifically discussed. A dynamic-programming algorithm and its improved version for CLIQUE are reviewed and some additional analysis is presented. The analysis implies that the improved algorithm, HEWN (hierarchical edge-weighted network), only provides a heuristic or useful method, but cannot be called a polynomial algorithm.


algorithm NP-hardness approximation ratio dynamic programming complexity 


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Copyright information

© Science Press, Beijing China and Allerton Press Inc. 2001

Authors and Affiliations

  1. 1.Department of Computer ScienceShandong UniversityJinanP.R. China

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