Class LongClausesDatabase

    • Field Detail

      • DEFAULT_INITIAL_NUMBER_OF_CLAUSES

        private static final int DEFAULT_INITIAL_NUMBER_OF_CLAUSES
        See Also:
        Constant Field Values
      • currentIndex

        private int currentIndex
      • clauses

        private int[][] clauses
      • literalsCache

        private int[][] literalsCache
      • generator

        java.util.Random generator
        Put it one place so there is only one Random generator for the whole SAT solver. TODO: Radek.
    • Constructor Detail

      • LongClausesDatabase

        public LongClausesDatabase()
    • Method Detail

      • addClause

        public int addClause​(int[] clause,
                             boolean isModel)
        Description copied from interface: ClauseDatabaseInterface
        It adds a clause to the database. This can change the state of the solver, for example if the clause is unsatisfiable in the current trail affectation, the solver will get in the conflict state.
        Parameters:
        clause - the clause to add
        isModel - defined if the clause is model clause
        Returns:
        the unique ID referring to the clause
      • assertLiteral

        public void assertLiteral​(int literal)
        Description copied from interface: ClauseDatabaseInterface
        It informs the ClausesDatabase that this literal is set, so that it can perform unit propagation.
        Parameters:
        literal - the literal that is set
      • removeClause

        public void removeClause​(int clauseId)
        Description copied from interface: ClauseDatabaseInterface
        It removes the clause which unique ID is @param clauseId.
        Parameters:
        clauseId - clause id
      • canRemove

        public boolean canRemove​(int clauseId)
        Description copied from interface: ClauseDatabaseInterface
        It tells if the implementation of ClausesDatabase can remove clauses or not
        Parameters:
        clauseId - the unique Id of the clause
        Returns:
        true iff removal of clauses is possible
      • resolutionWith

        public MapClause resolutionWith​(int clauseIndex,
                                        MapClause clause)
        Description copied from interface: ClauseDatabaseInterface
        It returns the clause obtained by resolution between clauseIndex and clause. It will also modify in place the given SetClause (avoid allocating).
        Parameters:
        clauseIndex - the unique id of the clause
        clause - an explanation clause that is modified by resolution
        Returns:
        the clause obtained by resolution
      • backjump

        public void backjump​(int level)
        Description copied from interface: ClauseDatabaseInterface
        Do everything needed to return to the given level.
        Parameters:
        level - the level to return to. Must be < solver.getCurrentLevel().
      • rateThisClause

        public int rateThisClause​(int[] clause)
        Description copied from class: AbstractClausesDatabase
        Indicates how much this database is optimized for this clause. The Database that gives the higher rank will get the clause.
        Specified by:
        rateThisClause in class AbstractClausesDatabase
        Parameters:
        clause - a clause to rate
        Returns:
        a non negative integer indicating how much the database is interested in this clause
      • ensureSize

        public void ensureSize​(int size)
        be sure that the database can contain numberOfClauses clauses
        Parameters:
        size - the size of the database to be ensured
      • isSatisfied

        private final boolean isSatisfied​(int literal)
        is the literal at position @param literalPos satisfied in current trail ?
      • isActiveOrSatisfied

        private final boolean isActiveOrSatisfied​(int literal)
        is the literal at position @param literalPos satisfied or active ?
      • isActive

        private final boolean isActive​(int literal)
        is the literal at position @param literalPos satisfied or active ?
      • toCNF

        public void toCNF​(java.io.BufferedWriter output)
                   throws java.io.IOException
        Description copied from class: AbstractClausesDatabase
        It creates a CNF description of the clauses stored in this database.
        Specified by:
        toCNF in interface ClauseDatabaseInterface
        Specified by:
        toCNF in class AbstractClausesDatabase
        Parameters:
        output - it specifies the target to which the description will be written.
        Throws:
        java.io.IOException - execption from java.io package