Azucar: A SAT-Based CSP Solver Using Compact Order Encoding

(Tool Presentation)
  • Tomoya Tanjo
  • Naoyuki Tamura
  • Mutsunori Banbara
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7317)


This paper describes a SAT-based CSP solver Azucar. Azucar solves a finite CSP by encoding it into a SAT instance using the compact order encoding and then solving the encoded SAT instance with an external SAT solver. In the compact order encoding, each integer variable is represented by using a numeral system of base B ≥ 2 and each digit is encoded by using the order encoding. Azucar is developed as a new version of an award-winning SAT-based CSP solver Sugar. Through some experiments, we confirmed Azucar can encode and solve very large domain sized CSP instances which Sugar can not encode, and shows better performance for Open-shop scheduling problems and the Cabinet problems of the CSP Solver Competition benchmark.


Constraint Satisfaction Problem Integer Variable Propositional Variable Numeral System Strip Packing Problem 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Tomoya Tanjo
    • 1
  • Naoyuki Tamura
    • 2
  • Mutsunori Banbara
    • 2
  1. 1.Transdisciplinary Research Integration CenterJapan
  2. 2.Information Science and Technology CenterKobe UniversityJapan

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