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The logic of search algorithms: Theory and applications

  • Ian P. Gent
  • Judith L. Underwood
Session 2a
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1330)

Abstract

Many search algorithms have been introduced without correctness proofs, or proved only with respect to an informal semantics of the algorithm. We address this problem by taking advantage of the correspondence between programs and proofs. We give a single proof of the correctness of a very general search algorithm, for which we provide Scheme code. It is straightforward to implement service functions to implement algorithms such as Davis-Putnam for satisfiability or forward checking (FC) for constraint satisfaction, and to incorporate conflict-directed backjumping (CBJ) and heuristics for variable and value ordering. By separating the search algorithm from problem features, our work should enable the much speedier implementation of sophisticated search methods such as FC-CBJ in new domains, and we illustrate this by sketching an implementation for the Hamiltonian Circuit problem.

Keywords

Constraint Satisfaction Problem Recursive Call Correctness Proof Partial Assignment Unit Clause 
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 1997

Authors and Affiliations

  • Ian P. Gent
    • 1
  • Judith L. Underwood
    • 2
  1. 1.APES Research Group, Department of Computer ScienceUniversity of StrathclydeGlasgowUK
  2. 2.BeAUTy Research Group, Department of Computing ScienceUniversity of GlasgowGlasgowUK

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