Solving Constraint Satisfaction Problems with SAT Technology

  • Naoyuki Tamura
  • Tomoya Tanjo
  • Mutsunori Banbara
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6009)


A Boolean Satisfiability Testing Problem (SAT) is a combinatorial problem to find a Boolean variable assignment which satisfies all given Boolean formulas. Recent performance improvement of SAT technologies makes SAT-based approaches applicable for solving hard and practical combinatorial problems, such as planning, scheduling, hardware/software verification, and constraint satisfaction.

Sugar is a SAT-based constraint solver based on a new encoding method called order encoding which was first used to encode job-shop scheduling problems by Crawford and Baker. In the order encoding, a comparison x ≤ a is encoded by a different Boolean variable for each integer variable x and integer value a. The Sugar solver shows a good performance for a wide variety of problems, and became the winner of the GLOBAL categories in 2008 and 2009 CSP solver competitions.

The talk will provide an introduction to modern SAT solvers, SAT encodings, implementation techniques of the Sugar solver, and its performance evaluation.


Schedule Problem Constraint Satisfaction Combinatorial Problem Constraint Satisfaction Problem Support Point 
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 2010

Authors and Affiliations

  • Naoyuki Tamura
    • 1
  • Tomoya Tanjo
    • 2
  • Mutsunori Banbara
    • 1
  1. 1.Information Science and Technology CenterKobe UniversityJapan
  2. 2.Graduate School of EngineeringKobe UniversityJapan

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