chuffed-flatzinc - 0.13.1-1+b1 main

Chuffed is a state of the art lazy clause solver designed from the
ground up with lazy clause generation in mind. Lazy clause generation
is a hybrid approach to constraint solving that combines features of
finite domain propagation and Boolean satisfiability. It combines
some of the advantages of finite domain constraint programming (high
level model and programmable search) with some of the advantages of
SAT solvers (reduced search by nogood creation, and effective
autonomous search using variable activities).
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Chuffed only supports 3 different propagator priorities. Chuffed
implements a number of global propagators (alldiff, inverse, minimum,
table, regular, mdd, cumulative, disjunctive, circuit,
difference). It also only supports two kinds of integer
variables. Small integer variables for which the domain is
represented by a byte string. And large integer variables for which
the domain is represented only by its upper and lower bound (no holes
allowed). All boolean variables and boolean constraints are handled
by the builtin SAT solver.
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The solver, when run with lazy clause generation disabled, is
somewhat comparable in speed with older versions of Gecode. The
overhead from lazy clause generation ranges from negligible to
perhaps around 100%. The search reduction, however, can reach orders
of magnitude on appropriate problems. Thus lazy clause generation is
an extremely important and useful technology.
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This package provides a FlatZinc implementation, to be used as a
MiniZinc backend.