Searching for Nacro Operators with Automatically Generated Heuristics

  • István T. Hernádvölgyi
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2056)


Macro search is used to derive solutions quickly for large search spaces at the expense of optimality. We present a novel way of building macro tables. Our contribution is twofold: (1) for the first time, we use automatically generated heuristics to find optimal macros, (2) due to the speed-up achieved by (1), we merge consecutive subgoals to reduce the solution lengths.We use the Rubik's Cube to demonstrate our techniques. For this puzzle, a 44% improvement of the average solution length was achieved over macro tables built with previous techniques.


Heuristic Search Goal State Solution Path Large Search Space Pattern Database 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • István T. Hernádvölgyi
    • 1
  1. 1.University of OttawaSchool of Information Technology & EngineeringOttawa, OntarioCanada

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