Method: ConstraintSolver::AllDifferentConstraint#revise_decomposed_local

Defined in:
lib/AllDifferentConstraint.rb

#revise_decomposed_local ⇒ Object Also known as: revise 



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# File 'lib/AllDifferentConstraint.rb', line 68

def revise_decomposed_local
    revisedVariables = []
    wipeout = false
    pruneList = Set.new
    assignedVariables, unassignedVariables = @variables.partition { |var| var.assigned? }
    pruneList.merge(assignedVariables.collect { |var| var.value })
    unassignedVariables.find_all { |var| var.domain.include_any?(pruneList) }.each { |var|
	begin
	    var.domain.prune(pruneList)
	rescue DomainWipeoutException
	    wipeout = true
	end
	revisedVariables << var
	break if wipeout
    }
    unless wipeout
	workQueue = unassignedVariables.find_all { |var| var.domain.size == 1 }
	while not workQueue.empty?
	    currentVariable = workQueue.shift
	    currentValue = currentVariable.domain.first
	    ((unassignedVariables - [ currentVariable ]).find_all { |var|
		var.domain.include?(currentValue)
	    }).each { |var|
		begin
		    var.domain.prune(currentValue)
		rescue DomainWipeoutException
		    wipeout = true
		end
		revisedVariables << var
		break if wipeout
		workQueue << var if var.domain.size == 1
	    }
	end

	unless wipeout
	    # check satisfiability
	    valueList = Set.new
	    unassignedVariables.each { |var|
		valueList.merge(var.values)
	    }
	    if unassignedVariables.size > valueList.size
		wipeout = true
	    end
	end
    end
    return revisedVariables, 0, wipeout
end