A Sufficient Condition for Backtrack-Free Search

  title={A Sufficient Condition for Backtrack-Free Search},
  author={Eugene C. Freuder},
  journal={J. ACM},
A constraint satisfaction problem revolves finding values for a set of variables subject to a set of constraints (relations) on those variables Backtrack search is often used to solve such problems. A relationship involving the structure of the constraints is described which characterizes to some degree the extreme case of mimmum backtracking (none) The relationship involves a concept called "width," which may provide some guidance in the representation of constraint satisfaction problems and… 

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