source: vis_dev/sharpSAT/src/src_sharpSAT/MainSolver/MainSolver.h

#ifndef MAINSOLVER_H
#define MAINSOLVER_H

//shared files
#include <Interface/AnalyzerData.h>

#include "../Basics.h"
#include "InstanceGraph/InstanceGraph.h"

#include "FormulaCache.h"


/** \addtogroup Interna Solver Interna 
 * Dies sind alle Klassen, die ausschlieï¿œich vom Solver selbst verwendet werden
 * sollten.
 */
 
 
/*@{*/

typedef unsigned char viewStateT;
#define   NIL  0
#define   IN_SUP_COMP  1
#define   SEEN 2
#define   IN_OTHER_COMP  3

enum retStateT{

        EXIT,
        RESOLVED,
        PROCESS_COMPONENT
}; 

enum retIBCPT
{
        NOTHING_FOUND,
        FOUND,
        CONTRADICTION,
}; 


class CMainSolver : public CInstanceGraph
{  
   CDecisionStack decStack; // decision stack               
   CStopWatch   stopWatch;  
   
   CFormulaCache xFormulaCache;  
   vector<AntAndLit> bcpImplQueue;               
   
   int lastTimeCClDeleted;
   int lastCClCleanUp;
   
   unsigned int remPoll;
   
   retStateT backTrack();   
   
   // removes all cachePollutions that might be present in decedants of comnponents from the 
   // present decision level   
   void removeAllCachePollutions();
   
    
   bool findVSADSDecVar(LiteralIdT &theLit, const CComponentId & superComp);

   
   bool decide();
   
   bool bcp();    
 
   void handleSolution()
   {   
      int actCompVars = 0;
      static CRealNum rnCodedSols;

      // in fact the active component should only contain active vars   
      if(decStack.TOS_countRemComps() != 0)
        actCompVars = decStack.TOS_NextComp().countVars();
     
      pow2(rnCodedSols, actCompVars);   
      decStack.top().includeSol(rnCodedSols);         
      theRunAn.addValue(SOLUTION, decStack.getDL());                    

   }
   
   retStateT resolveConflict();    
   
   SOLVER_StateT countSAT();   
    
   bool performPreProcessing(); 
  
   
   /**
     *  passes a componentId to rComp that is made of all
     *  active variables and clauses
     *  !! used to initialize decStack at DL zero
    **/ 
   void makeCompIdFromActGraph(CComponentId& rComp);
   
   // BEGIN component analysis   
   vector<VarIdT> componentSearchStack;     
   bool recordRemainingComps();    
   bool getComp(const VarIdT &theVar, 
                            const CComponentId &superComp, 
                            viewStateT lookUpCls[],
                            viewStateT lookUpVars[]);
   // END component analysis
   
   void printComponent(const CComponentId& rComp);
    
      
   inline bool assignVal(const LiteralIdT &rLitId, AntecedentT ant = AntecedentT(NOT_A_CLAUSE))
   {
      return getVar(rLitId).setVal(rLitId.polarity(), decStack.getDL(), ant);
   }
   
   bool BCP(vector<AntAndLit> &thePairsOfImpl);
   
   /////////////////////////////////////////////
   //  BEGIN conflict analysis
   /////////////////////////////////////////////
   
  private:
    
   vector<LiteralIdT> theQueue;       
   vector<LiteralIdT> ca_1UIPClause;    
   vector<LiteralIdT> ca_lastUIPClause;    
        
   int imaxDecLev;        
    
   // includes the causes of a variable assignment via 
   // breadth first search
   void caIncludeCauses(LiteralIdT theLit, bool viewedVars[]);       
   void caIncorporateLit(const LiteralIdT &Lit, bool viewedVars[]); 
  
   void caAddtoCauses(LiteralIdT theLit, bool viewedVars[]);
   // initializes all data structures for the analysis
   // especially the startin point of the analysis i plugged into the queue
   bool caInit(vector<AntecedentT> & theConflicted, bool viewedVars[]); 

 
   bool caGetCauses_lastUIP(vector<AntecedentT> & theConflicted);
   bool caGetCauses_firstUIP(vector<AntecedentT> & theConflicted);
   
   // whenever a variable that is not implied causes a conflict
   // the conflict clause generated from this conflict implies a flip
   // of that variable:
   // creation of that clause and recording the implication is done by:
   
   const vector<LiteralIdT> &caGetPrev1UIPCCl()
   {
      return ca_1UIPClause;
   }
   const vector<LiteralIdT> &caGetPrevLastUIPCCl()
   {
      return ca_lastUIPClause;
   }

   /// ermittelt den maximalen Entscheidungslevel von
   /// Variablen die zu den Konfliktursachen gehï¿œen.
   /// Ein Aufruf ist erst nach dem Auftruf von getCausesOf sinnvoll
   int getMaxDecLevFromAnalysis() const {return imaxDecLev;}
   
   /// gibt KonfliktKlausel zurck die durch die
   /// vorhergehende Analyse gewonnen wurde
   bool create1UIPCCl()
   {
      return createConflictClause(ca_1UIPClause);
   }
   
   bool createLastUIPCCl()
   {
      return createConflictClause(ca_lastUIPClause);
   }
   
   /////////////////////////////////////////////
   //  END conflict analysis
   /////////////////////////////////////////////
     
   /////////////////////////////////////////////
   //  BEGIN implicitBCP
   /////////////////////////////////////////////
   
   ///  this method is used for heuristically testing variable assignments
   ///  whether they incur a conflict. If so we can infer the opposite assignment of
   ///  the variable in question
   ///  Thus the method will then perform the assignment
   ///  Furthermore it manages the necessary entries to the decision stack itself
   ///  returned value: analogously to the bcp procedure: false iff a conflict is found
   bool implicitBCP();   
   
   bool createAntClauseFor(const LiteralIdT &Lit);   
   
   /////////////////////////////////////////////
   //  END implicitBCP
   /////////////////////////////////////////////
   
   /////////////////////////////////////////////
   // BEGIN PreProcessing methods
   ////////////////////////////////////////////
   
   ///NOTE: Preprocessing methods assume that no conflict clauses are present !
   
   bool prep_IBCP(vector<AntAndLit> &impls);
   /// Preprocessing
   /// i.e. the "hard" version of ImplicitBCP
   /// used for preprosessing ONLY
   bool prepFindHiddenBackBoneLits();
   
   /// Apply the BCP rule in a Preprocessing step:
   /// That is: if firstLit is a valid literal, propagation is started there
   /// firstLit should not be assigned already!
   /// furthermore ALL unit clauses are processed
   bool prepBCP(LiteralIdT firstLit = NOT_A_LIT);

   /////////////////////////////////////////////
   // END PreProcessing methods
   /////////////////////////////////////////////
   
   bool printUnitClauses();   
 
 public:
   
   // class constructor
   CMainSolver();   
   
   // class destructor
   ~CMainSolver();      
   
   void solve(const char *lpstrFileName); 
   
   void setTimeBound(long int i)
   {
      stopWatch.setTimeBound(i);
   }

};


/*@}*/
#endif // SOLVER_H