We study the computational complexity of binary valued constraint satisfaction problems (VCSP) given by allowing only certain types of costs in every triangle of variable-value assignments to three distinct variables. We show that for several computational problems, including CSP, Max-CSP, finite-valued VCSP, and general-valued VCSP, the only non-trivial tractable classes are the well known maximum matching problem and the recently discovered joint-winner property [9].


Constraint Satisfaction Problem Cost Type Tractable Case Constraint Satisfaction Problem Instance Unary Cost 
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© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Martin C. Cooper
    • 1
  • Stanislav Živný
    • 2
  1. 1.IRITUniversity of Toulouse IIIToulouseFrance
  2. 2.University CollegeUniversity of OxfordUK

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