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C. Castro
strategy Solved_Form
repeat
dont care choose (
dont care choose (Node-Consistency)
k
dont care choose (Arc-Consistency)
k
dont care choose (Instantiation)
k
dont care choose (Elimination)
k
dont care choose (Falsity)
k
dont know choose (Generate)
)
endrepeat
end of strategy
Fig. A.3. Strategy Solved_Form
with at least one element in the list of unary and binary constraints. Strategy Strategy_Node-Consistency uses rule GetUnaryConstraint to get the rst
unary constraint in the list of unary and binary constraints. If there exists a
unary constraint the strategy will apply rule Node-Consistency_1, if the variable involved in the unary constraint is in the list of membership constraints,
or rule Node-Consistency_2, if the variable is in the list of equality constraints.
In the set ConstraintSolving we use only one rule to verify node consistency,
but we have implemented two versions sligtly dierents. This is an implementation choice, as we have a list for the membership constraints and another
one for the equality constraints, it is easy to prote this information. The
same explanation is valid for arc consistency, where we have created four rules
to implement the general version presented in the set ConstraintSolving.
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