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A CSP Search Algorithm with Reduced Branching Factor

  • Igor Razgon
  • Amnon Meisels
Conference paper
  • 175 Downloads
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3978)

Abstract

This paper presents an attempt to construct a ”practical” CSP algorithm that assigns a variable with 2 values at every step. Such a strategy has been successfully used for construction of ”theoretical” constraint solvers because it decreases twice the base of the exponent of the upper bound of the search algorithm.

We present a solver based on the strategy. The pruning mechanism of the algorithm resembles Forward Checking (FC), therefore we term it 2FC. According to our experimental evaluation, 2FC outperforms FC on graph coloring problems and on non-dense instances of randomly generated CSPs.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Igor Razgon
    • 1
  • Amnon Meisels
    • 1
  1. 1.Department of Computer ScienceBen-Gurion University of the NegevBeer-ShevaIsrael

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