Experiments with SAT sweeping.

11 files changed, 3794 insertions, 14 deletions

diff --git a/abclib.dsp b/abclib.dsp
index 23c2ce28..cf6e46e8 100644
--- a/abclib.dsp
+++ b/abclib.dsp
@@ -4931,6 +4931,14 @@ SOURCE=.\src\aig\gia\giaCSatOld.c
 # End Source File
 # Begin Source File
 
+SOURCE=.\src\aig\gia\giaCSatP.c
+# End Source File
+# Begin Source File
+
+SOURCE=.\src\aig\gia\giaCSatP.h
+# End Source File
+# Begin Source File
+
 SOURCE=.\src\aig\gia\giaCTas.c
 # End Source File
 # Begin Source File
@@ -5587,6 +5595,10 @@ SOURCE=.\src\proof\cec\cecSatG2.c
 # End Source File
 # Begin Source File
 
+SOURCE=.\src\proof\cec\cecSatG3.c
+# End Source File
+# Begin Source File
+
 SOURCE=.\src\proof\cec\cecSeq.c
 # End Source File
 # Begin Source File
diff --git a/src/aig/gia/giaCSatP.c b/src/aig/gia/giaCSatP.c
new file mode 100644
index 00000000..00ab880b
--- /dev/null
+++ b/src/aig/gia/giaCSatP.c
@@ -0,0 +1,1209 @@
+/**CFile****************************************************************
+
+  FileName    [giaCSat.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Scalable AIG package.]
+
+  Synopsis    [A simple circuit-based solver.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - June 20, 2005.]
+
+  Revision    [$Id: giaCSat.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "gia.h"
+#include "giaCSatP.h"
+
+ABC_NAMESPACE_IMPL_START
+
+
+//#define gia_assert(exp)     ((void)0)
+//#define gia_assert(exp)     (assert(exp))
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+
+static inline int   CbsP_VarIsAssigned( Gia_Obj_t * pVar )      { return pVar->fMark0;                        }
+static inline void  CbsP_VarAssign( Gia_Obj_t * pVar )          { assert(!pVar->fMark0); pVar->fMark0 = 1;    }
+static inline void  CbsP_VarUnassign( CbsP_Man_t * pMan, Gia_Obj_t * pVar )        { assert(pVar->fMark0);  pVar->fMark0 = 0; pVar->fMark1 = 0; pMan->vValue->pArray[Gia_ObjId(pMan->pAig,pVar)] = ~0; }
+static inline int   CbsP_VarValue( Gia_Obj_t * pVar )           { assert(pVar->fMark0);  return pVar->fMark1; }
+static inline void  CbsP_VarSetValue( Gia_Obj_t * pVar, int v ) { assert(pVar->fMark0);  pVar->fMark1 = v;    }
+static inline int   CbsP_VarIsJust( Gia_Obj_t * pVar )          { return Gia_ObjIsAnd(pVar) && !CbsP_VarIsAssigned(Gia_ObjFanin0(pVar)) && !CbsP_VarIsAssigned(Gia_ObjFanin1(pVar)); } 
+static inline int   CbsP_VarFanin0Value( Gia_Obj_t * pVar )     { return !CbsP_VarIsAssigned(Gia_ObjFanin0(pVar)) ? 2 : (CbsP_VarValue(Gia_ObjFanin0(pVar)) ^ Gia_ObjFaninC0(pVar)); }
+static inline int   CbsP_VarFanin1Value( Gia_Obj_t * pVar )     { return !CbsP_VarIsAssigned(Gia_ObjFanin1(pVar)) ? 2 : (CbsP_VarValue(Gia_ObjFanin1(pVar)) ^ Gia_ObjFaninC1(pVar)); }
+
+static inline int         CbsP_VarDecLevel( CbsP_Man_t * p, Gia_Obj_t * pVar )  { int Value = p->vValue->pArray[Gia_ObjId(p->pAig,pVar)]; assert( Value != ~0 ); return Vec_IntEntry(p->vLevReas, 3*Value);          }
+static inline Gia_Obj_t * CbsP_VarReason0( CbsP_Man_t * p, Gia_Obj_t * pVar )   { int Value = p->vValue->pArray[Gia_ObjId(p->pAig,pVar)]; assert( Value != ~0 ); return pVar + Vec_IntEntry(p->vLevReas, 3*Value+1); }
+static inline Gia_Obj_t * CbsP_VarReason1( CbsP_Man_t * p, Gia_Obj_t * pVar )   { int Value = p->vValue->pArray[Gia_ObjId(p->pAig,pVar)]; assert( Value != ~0 ); return pVar + Vec_IntEntry(p->vLevReas, 3*Value+2); }
+static inline int         CbsP_ClauseDecLevel( CbsP_Man_t * p, int hClause )    { return CbsP_VarDecLevel( p, p->pClauses.pData[hClause] );                               }
+
+#define CbsP_QueForEachEntry( Que, pObj, i )                         \
+    for ( i = (Que).iHead; (i < (Que).iTail) && ((pObj) = (Que).pData[i]); i++ )
+
+#define CbsP_ClauseForEachVar( p, hClause, pObj )                    \
+    for ( (p)->pIter = (p)->pClauses.pData + hClause; (pObj = *pIter); (p)->pIter++ )
+#define CbsP_ClauseForEachVar1( p, hClause, pObj )                   \
+    for ( (p)->pIter = (p)->pClauses.pData+hClause+1; (pObj = *pIter); (p)->pIter++ )
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    [Sets default values of the parameters.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void CbsP_SetDefaultParams( CbsP_Par_t * pPars )
+{
+    memset( pPars, 0, sizeof(CbsP_Par_t) );
+    pPars->nBTLimit    =  1000;   // limit on the number of conflicts
+    pPars->nJustLimit  =   100;   // limit on the size of justification queue
+    pPars->fUseHighest =     1;   // use node with the highest ID
+    pPars->fUseLowest  =     0;   // use node with the highest ID
+    pPars->fUseMaxFF   =     0;   // use node with the largest fanin fanout
+    pPars->fVerbose    =     1;   // print detailed statistics
+
+    pPars->fUseProved  =     1;
+
+
+    pPars->nJscanThis     = 0;
+    pPars->nRscanThis     = 0;
+    pPars->maxJscanUndec  = 0;
+    pPars->maxRscanUndec  = 0;
+    pPars->maxJscanSolved = 0;
+    pPars->maxRscanSolved = 0;
+
+
+    pPars->accJscanSat    = 0;
+    pPars->accJscanUnsat  = 0;
+    pPars->accJscanUndec  = 0;
+    pPars->accRscanSat    = 0;
+    pPars->accRscanUnsat  = 0;
+    pPars->accRscanUndec  = 0;
+    pPars->nSat    = 0;
+    pPars->nUnsat  = 0;
+    pPars->nUndec  = 0;
+
+    pPars->nJscanLimit    = 100;
+    pPars->nRscanLimit    = 100;
+    pPars->nPropLimit     = 500;
+}
+void CbsP_ManSetConflictNum( CbsP_Man_t * p, int Num )
+{
+    p->Pars.nBTLimit = Num;
+}
+
+static inline void CbsP_UpdateRecord( CbsP_Par_t * pPars, int res ){
+    if( CBS_UNDEC == res ){
+        pPars->nUndec ++ ;
+        if( pPars-> maxJscanUndec < pPars->nJscanThis )
+            pPars-> maxJscanUndec = pPars->nJscanThis; 
+        if( pPars-> maxRscanUndec < pPars->nRscanThis )
+            pPars-> maxRscanUndec = pPars->nRscanThis; 
+        if( pPars->  maxPropUndec < pPars->nPropThis )
+            pPars->  maxPropUndec = pPars->nPropThis; 
+
+        pPars->accJscanUndec     += pPars->nJscanThis;
+        pPars->accRscanUndec     += pPars->nRscanThis;
+        pPars-> accPropUndec     += pPars->nPropThis;
+    } else {
+        if( pPars->maxJscanSolved < pPars->nJscanThis )
+            pPars->maxJscanSolved = pPars->nJscanThis; 
+        if( pPars->maxRscanSolved < pPars->nRscanThis )
+            pPars->maxRscanSolved = pPars->nRscanThis; 
+        if( pPars-> maxPropSolved < pPars->nPropThis )
+            pPars-> maxPropSolved = pPars->nPropThis; 
+        if( CBS_SAT == res ){
+            pPars->nSat ++ ;
+            pPars->accJscanSat   += pPars->nJscanThis;
+            pPars->accRscanSat   += pPars->nRscanThis;
+            pPars-> accPropSat   += pPars->nPropThis;
+        } else
+        if( CBS_UNSAT == res ){
+            pPars->nUnsat ++ ;
+            pPars->accJscanUnsat += pPars->nJscanThis;
+            pPars->accRscanUnsat += pPars->nRscanThis;
+            pPars-> accPropUnsat += pPars->nPropThis;
+        }
+    }
+
+}
+
+void CbsP_PrintRecord( CbsP_Par_t * pPars ){
+    printf("max of solved: jscan# %13d rscan %13d prop %13d\n"   , pPars->maxJscanSolved, pPars->maxRscanSolved , pPars->maxPropSolved );
+    printf("max of  undec: jscan# %13d rscan %13d prop %13d\n"   , pPars->maxJscanUndec , pPars->maxRscanUndec  , pPars->maxPropUndec  );
+    printf("acc of    sat: jscan# %13ld rscan %13ld prop %13ld\n", pPars->accJscanSat   , pPars->accRscanSat    , pPars->accPropSat    );
+    printf("acc of  unsat: jscan# %13ld rscan %13ld prop %13ld\n", pPars->accJscanUnsat , pPars->accRscanUnsat  , pPars->accPropUnsat  );
+    printf("acc of  undec: jscan# %13ld rscan %13ld prop %13ld\n", pPars->accJscanUndec , pPars->accRscanUndec  , pPars->accPropUndec  );
+    if( pPars->nSat )
+        printf("avg of    sat: jscan# %13ld rscan %13ld prop %13ld\n", pPars->accJscanSat   / pPars->nSat   , pPars->accRscanSat   / pPars->nSat   , pPars->accPropSat   / pPars->nSat   );
+    if( pPars->nUnsat )
+        printf("avg of  unsat: jscan# %13ld rscan %13ld prop %13ld\n", pPars->accJscanUnsat / pPars->nUnsat , pPars->accRscanUnsat / pPars->nUnsat , pPars->accPropUnsat / pPars->nUnsat );
+    if( pPars->nUndec )
+        printf("avg of  undec: jscan# %13ld rscan %13ld prop %13ld\n", pPars->accJscanUndec / pPars->nUndec , pPars->accRscanUndec / pPars->nUndec , pPars->accPropUndec / pPars->nUndec );
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+CbsP_Man_t * CbsP_ManAlloc( Gia_Man_t * pGia )
+{
+    CbsP_Man_t * p;
+    p = ABC_CALLOC( CbsP_Man_t, 1 );
+    p->pProp.nSize = p->pJust.nSize = p->pClauses.nSize = 10000;
+    p->pProp.pData = ABC_ALLOC( Gia_Obj_t *, p->pProp.nSize );
+    p->pJust.pData = ABC_ALLOC( Gia_Obj_t *, p->pJust.nSize );
+    p->pClauses.pData = ABC_ALLOC( Gia_Obj_t *, p->pClauses.nSize );
+    p->pClauses.iHead = p->pClauses.iTail = 1;
+    p->vModel   = Vec_IntAlloc( 1000 );
+    p->vLevReas = Vec_IntAlloc( 1000 );
+    p->vTemp    = Vec_PtrAlloc( 1000 );
+    p->pAig     = pGia;
+    p->vValue   = Vec_IntAlloc( Gia_ManObjNum(pGia) );
+    Vec_IntFill( p->vValue, Gia_ManObjNum(pGia), ~0 );
+    //memset( p->vValue->pArray, (unsigned) ~0, sizeof(int) * Gia_ManObjNum(pGia) );
+    CbsP_SetDefaultParams( &p->Pars );
+    return p;
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void CbsP_ManStop( CbsP_Man_t * p )
+{
+    Vec_IntFree( p->vLevReas );
+    Vec_IntFree( p->vModel );
+    Vec_PtrFree( p->vTemp );
+    Vec_IntFree( p->vValue );
+    ABC_FREE( p->pClauses.pData );
+    ABC_FREE( p->pProp.pData );
+    ABC_FREE( p->pJust.pData );
+    ABC_FREE( p );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Returns satisfying assignment.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Vec_Int_t * CbsP_ReadModel( CbsP_Man_t * p )
+{
+    return p->vModel;
+}
+
+
+
+
+/**Function*************************************************************
+
+  Synopsis    [Returns 1 if the solver is out of limits.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+
+static inline int CbsP_ManCheckPropLimits( CbsP_Man_t * p )
+{
+    return p->Pars.nPropThis > p->Pars.nPropLimit;
+}
+static inline int CbsP_ManCheckLimits( CbsP_Man_t * p )
+{
+    return CbsP_ManCheckPropLimits(p) || p->Pars.nJscanThis > p->Pars.nJscanLimit || p->Pars.nRscanThis > p->Pars.nRscanLimit || p->Pars.nJustThis > p->Pars.nJustLimit || p->Pars.nBTThis > p->Pars.nBTLimit;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Saves the satisfying assignment as an array of literals.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline void CbsP_ManSaveModel( CbsP_Man_t * p, Vec_Int_t * vCex )
+{
+    Gia_Obj_t * pVar;
+    int i;
+    Vec_IntClear( vCex );
+    p->pProp.iHead = 0;
+    CbsP_QueForEachEntry( p->pProp, pVar, i )
+        if ( Gia_ObjIsCi(pVar) )
+            Vec_IntPush( vCex, Abc_Var2Lit(Gia_ObjId(p->pAig,pVar), !CbsP_VarValue(pVar)) );
+//            Vec_IntPush( vCex, Abc_Var2Lit(Gia_ObjCioId(pVar), !CbsP_VarValue(pVar)) );
+} 
+static inline void CbsP_ManSaveModelAll( CbsP_Man_t * p, Vec_Int_t * vCex )
+{
+    Gia_Obj_t * pVar;
+    int i;
+    Vec_IntClear( vCex );
+    p->pProp.iHead = 0;
+    CbsP_QueForEachEntry( p->pProp, pVar, i )
+        Vec_IntPush( vCex, Abc_Var2Lit(Gia_ObjId(p->pAig,pVar), !CbsP_VarValue(pVar)) );
+} 
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int CbsP_QueIsEmpty( CbsP_Que_t * p )
+{
+    return p->iHead == p->iTail;
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline void CbsP_QuePush( CbsP_Que_t * p, Gia_Obj_t * pObj )
+{
+    assert( !Gia_IsComplement(pObj) );
+    if ( p->iTail == p->nSize )
+    {
+        p->nSize *= 2;
+        p->pData = ABC_REALLOC( Gia_Obj_t *, p->pData, p->nSize ); 
+    }
+    p->pData[p->iTail++] = pObj;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Returns 1 if the object in the queue.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int CbsP_QueHasNode( CbsP_Que_t * p, Gia_Obj_t * pObj )
+{
+    Gia_Obj_t * pTemp;
+    int i;
+    CbsP_QueForEachEntry( *p, pTemp, i )
+        if ( pTemp == pObj )
+            return 1;
+    return 0;
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline void CbsP_QueStore( CbsP_Que_t * p, int * piHeadOld, int * piTailOld )
+{
+    int i;
+    *piHeadOld = p->iHead;
+    *piTailOld = p->iTail;
+    for ( i = *piHeadOld; i < *piTailOld; i++ )
+        CbsP_QuePush( p, p->pData[i] );
+    p->iHead = *piTailOld;
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline void CbsP_QueRestore( CbsP_Que_t * p, int iHeadOld, int iTailOld )
+{
+    p->iHead = iHeadOld;
+    p->iTail = iTailOld;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Finalized the clause.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int CbsP_QueFinish( CbsP_Que_t * p )
+{
+    int iHeadOld = p->iHead;
+    assert( p->iHead < p->iTail );
+    CbsP_QuePush( p, NULL );
+    p->iHead = p->iTail;
+    return iHeadOld;
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Max number of fanins fanouts.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int CbsP_VarFaninFanoutMax( CbsP_Man_t * p, Gia_Obj_t * pObj )
+{
+    int Count0, Count1;
+    assert( !Gia_IsComplement(pObj) );
+    assert( Gia_ObjIsAnd(pObj) );
+    Count0 = Gia_ObjRefNum( p->pAig, Gia_ObjFanin0(pObj) );
+    Count1 = Gia_ObjRefNum( p->pAig, Gia_ObjFanin1(pObj) );
+    return Abc_MaxInt( Count0, Count1 );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Find variable with the highest ID.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline Gia_Obj_t * CbsP_ManDecideHighest( CbsP_Man_t * p )
+{
+    Gia_Obj_t * pObj, * pObjMax = NULL;
+    int i;
+    CbsP_QueForEachEntry( p->pJust, pObj, i )
+        if ( pObjMax == NULL || pObjMax < pObj )
+            pObjMax = pObj;
+    return pObjMax;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Find variable with the lowest ID.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline Gia_Obj_t * CbsP_ManDecideLowest( CbsP_Man_t * p )
+{
+    Gia_Obj_t * pObj, * pObjMin = NULL;
+    int i;
+    CbsP_QueForEachEntry( p->pJust, pObj, i )
+        if ( pObjMin == NULL || pObjMin > pObj )
+            pObjMin = pObj;
+    return pObjMin;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Find variable with the maximum number of fanin fanouts.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline Gia_Obj_t * CbsP_ManDecideMaxFF( CbsP_Man_t * p )
+{
+    Gia_Obj_t * pObj, * pObjMax = NULL;
+    int i, iMaxFF = 0, iCurFF;
+    assert( p->pAig->pRefs != NULL );
+    CbsP_QueForEachEntry( p->pJust, pObj, i )
+    {
+        iCurFF = CbsP_VarFaninFanoutMax( p, pObj );
+        assert( iCurFF > 0 );
+        if ( iMaxFF < iCurFF )
+        {
+            iMaxFF = iCurFF;
+            pObjMax = pObj;
+        }
+    }
+    return pObjMax; 
+}
+
+
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline void CbsP_ManCancelUntil( CbsP_Man_t * p, int iBound )
+{
+    Gia_Obj_t * pVar;
+    int i;
+    assert( iBound <= p->pProp.iTail );
+    p->pProp.iHead = iBound;
+    CbsP_QueForEachEntry( p->pProp, pVar, i )
+        CbsP_VarUnassign( p, pVar );
+    p->pProp.iTail = iBound;
+    Vec_IntShrink( p->vLevReas, 3*iBound );
+}
+
+//int s_Counter = 0;
+
+/**Function*************************************************************
+
+  Synopsis    [Assigns the variables a value.]
+
+  Description [Returns 1 if conflict; 0 if no conflict.]
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline void CbsP_ManAssign( CbsP_Man_t * p, Gia_Obj_t * pObj, int Level, Gia_Obj_t * pRes0, Gia_Obj_t * pRes1 )
+{
+    Gia_Obj_t * pObjR = Gia_Regular(pObj);
+    assert( Gia_ObjIsCand(pObjR) );
+    assert( !CbsP_VarIsAssigned(pObjR) );
+    CbsP_VarAssign( pObjR );
+    CbsP_VarSetValue( pObjR, !Gia_IsComplement(pObj) );
+    assert( p->vValue->pArray[Gia_ObjId(p->pAig,pObjR)] == ~0 );
+    p->vValue->pArray[Gia_ObjId(p->pAig,pObjR)] = p->pProp.iTail;
+    CbsP_QuePush( &p->pProp, pObjR );
+    Vec_IntPush( p->vLevReas, Level );
+    Vec_IntPush( p->vLevReas, pRes0 ? pRes0-pObjR : 0 );
+    Vec_IntPush( p->vLevReas, pRes1 ? pRes1-pObjR : 0 );
+    assert( Vec_IntSize(p->vLevReas) == 3 * p->pProp.iTail );
+    if( pRes0 )
+        p->Pars.nPropThis ++ ;
+//    s_Counter++;
+//    s_Counter = Abc_MaxIntInt( s_Counter, Vec_IntSize(p->vLevReas)/3 );
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Returns clause size.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int CbsP_ManClauseSize( CbsP_Man_t * p, int hClause )
+{
+    CbsP_Que_t * pQue = &(p->pClauses);
+    Gia_Obj_t ** pIter;
+    for ( pIter = pQue->pData + hClause; *pIter; pIter++ );
+    return pIter - pQue->pData - hClause ;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Prints conflict clause.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline void CbsP_ManPrintClause( CbsP_Man_t * p, int Level, int hClause )
+{
+    CbsP_Que_t * pQue = &(p->pClauses);
+    Gia_Obj_t * pObj;
+    int i;
+    assert( CbsP_QueIsEmpty( pQue ) );
+    printf( "Level %2d : ", Level );
+    for ( i = hClause; (pObj = pQue->pData[i]); i++ )
+        printf( "%d=%d(%d) ", Gia_ObjId(p->pAig, pObj), CbsP_VarValue(pObj), CbsP_VarDecLevel(p, pObj) );
+    printf( "\n" );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Prints conflict clause.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline void CbsP_ManPrintClauseNew( CbsP_Man_t * p, int Level, int hClause )
+{
+    CbsP_Que_t * pQue = &(p->pClauses);
+    Gia_Obj_t * pObj;
+    int i;
+    assert( CbsP_QueIsEmpty( pQue ) );
+    printf( "Level %2d : ", Level );
+    for ( i = hClause; (pObj = pQue->pData[i]); i++ )
+        printf( "%c%d ", CbsP_VarValue(pObj)? '+':'-', Gia_ObjId(p->pAig, pObj) );
+    printf( "\n" );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Returns conflict clause.]
+
+  Description [Performs conflict analysis.]
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline void CbsP_ManDeriveReason( CbsP_Man_t * p, int Level )
+{
+    CbsP_Que_t * pQue = &(p->pClauses);
+    Gia_Obj_t * pObj, * pReason;
+    int i, k, iLitLevel;
+    assert( pQue->pData[pQue->iHead] == NULL );
+    assert( pQue->iHead + 1 < pQue->iTail );
+/*
+    for ( i = pQue->iHead + 1; i < pQue->iTail; i++ )
+    {
+        pObj = pQue->pData[i];
+        assert( pObj->fMark0 == 1 );
+    }
+*/
+    // compact literals
+    Vec_PtrClear( p->vTemp );
+    for ( i = k = pQue->iHead + 1; i < pQue->iTail; i++ )
+    {
+        pObj = pQue->pData[i];
+        if ( !pObj->fMark0 ) // unassigned - seen again
+            continue;
+        // assigned - seen first time
+        pObj->fMark0 = 0;
+        Vec_PtrPush( p->vTemp, pObj );
+        // check decision level
+        iLitLevel = CbsP_VarDecLevel( p, pObj );
+        if ( iLitLevel < Level )
+        {
+            pQue->pData[k++] = pObj;
+            continue;
+        }
+        assert( iLitLevel == Level );
+        pReason = CbsP_VarReason0( p, pObj );
+        if ( pReason == pObj ) // no reason
+        {
+            //assert( pQue->pData[pQue->iHead] == NULL );
+            pQue->pData[pQue->iHead] = pObj;
+            continue;
+        }
+        CbsP_QuePush( pQue, pReason );
+        pReason = CbsP_VarReason1( p, pObj );
+        if ( pReason != pObj ) // second reason
+            CbsP_QuePush( pQue, pReason );
+    }
+    assert( pQue->pData[pQue->iHead] != NULL );
+    pQue->iTail = k;
+    // clear the marks
+    Vec_PtrForEachEntry( Gia_Obj_t *, p->vTemp, pObj, i )
+        pObj->fMark0 = 1;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Returns conflict clause.]
+
+  Description [Performs conflict analysis.]
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int CbsP_ManAnalyze( CbsP_Man_t * p, int Level, Gia_Obj_t * pVar, Gia_Obj_t * pFan0, Gia_Obj_t * pFan1 )
+{
+    CbsP_Que_t * pQue = &(p->pClauses);
+    assert( CbsP_VarIsAssigned(pVar) );
+    assert( CbsP_VarIsAssigned(pFan0) );
+    assert( pFan1 == NULL || CbsP_VarIsAssigned(pFan1) );
+    assert( CbsP_QueIsEmpty( pQue ) );
+    CbsP_QuePush( pQue, NULL );
+    CbsP_QuePush( pQue, pVar );
+    CbsP_QuePush( pQue, pFan0 );
+    if ( pFan1 )
+        CbsP_QuePush( pQue, pFan1 );
+    CbsP_ManDeriveReason( p, Level );
+    return CbsP_QueFinish( pQue );
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Performs resolution of two clauses.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int CbsP_ManResolve( CbsP_Man_t * p, int Level, int hClause0, int hClause1 )
+{
+    CbsP_Que_t * pQue = &(p->pClauses);
+    Gia_Obj_t * pObj;
+    int i, LevelMax = -1, LevelCur;
+    assert( pQue->pData[hClause0] != NULL );
+    assert( pQue->pData[hClause0] == pQue->pData[hClause1] );
+/*
+    for ( i = hClause0 + 1; (pObj = pQue->pData[i]); i++ )
+        assert( pObj->fMark0 == 1 );
+    for ( i = hClause1 + 1; (pObj = pQue->pData[i]); i++ )
+        assert( pObj->fMark0 == 1 );
+*/
+    assert( CbsP_QueIsEmpty( pQue ) );
+    CbsP_QuePush( pQue, NULL );
+    for ( i = hClause0 + 1; (pObj = pQue->pData[i]); i++ )
+    {
+        if ( !pObj->fMark0 ) // unassigned - seen again
+            continue;
+        // assigned - seen first time
+        pObj->fMark0 = 0;
+        CbsP_QuePush( pQue, pObj );
+        p->Pars.nRscanThis ++ ;
+        LevelCur = CbsP_VarDecLevel( p, pObj );
+        if ( LevelMax < LevelCur )
+            LevelMax = LevelCur;
+    }
+    for ( i = hClause1 + 1; (pObj = pQue->pData[i]); i++ )
+    {
+        if ( !pObj->fMark0 ) // unassigned - seen again
+            continue;
+        // assigned - seen first time
+        pObj->fMark0 = 0;
+        CbsP_QuePush( pQue, pObj );
+        p->Pars.nRscanThis ++ ;
+        LevelCur = CbsP_VarDecLevel( p, pObj );
+        if ( LevelMax < LevelCur )
+            LevelMax = LevelCur;
+    }
+    for ( i = pQue->iHead + 1; i < pQue->iTail; i++ )
+        pQue->pData[i]->fMark0 = 1;
+    CbsP_ManDeriveReason( p, LevelMax );
+    return CbsP_QueFinish( pQue );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Propagates a variable.]
+
+  Description [Returns clause handle if conflict; 0 if no conflict.]
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int CbsP_ManPropagateOne( CbsP_Man_t * p, Gia_Obj_t * pVar, int Level )
+{
+    int Value0, Value1;
+    assert( !Gia_IsComplement(pVar) );
+    assert( CbsP_VarIsAssigned(pVar) );
+    if ( Gia_ObjIsCi(pVar) )
+        return 0;
+    assert( Gia_ObjIsAnd(pVar) );
+    Value0 = CbsP_VarFanin0Value(pVar);
+    Value1 = CbsP_VarFanin1Value(pVar);
+    if ( CbsP_VarValue(pVar) )
+    { // value is 1
+        if ( Value0 == 0 || Value1 == 0 ) // one is 0
+        {
+            if ( Value0 == 0 && Value1 != 0 )
+                return CbsP_ManAnalyze( p, Level, pVar, Gia_ObjFanin0(pVar), NULL );
+            if ( Value0 != 0 && Value1 == 0 )
+                return CbsP_ManAnalyze( p, Level, pVar, Gia_ObjFanin1(pVar), NULL );
+            assert( Value0 == 0 && Value1 == 0 );
+            return CbsP_ManAnalyze( p, Level, pVar, Gia_ObjFanin0(pVar), Gia_ObjFanin1(pVar) );
+        }
+        if ( Value0 == 2 ) // first is unassigned
+            CbsP_ManAssign( p, Gia_ObjChild0(pVar), Level, pVar, NULL );
+        if ( Value1 == 2 ) // first is unassigned
+            CbsP_ManAssign( p, Gia_ObjChild1(pVar), Level, pVar, NULL );
+        return 0;
+    }
+    // value is 0
+    if ( Value0 == 0 || Value1 == 0 ) // one is 0
+        return 0;
+    if ( Value0 == 1 && Value1 == 1 ) // both are 1
+        return CbsP_ManAnalyze( p, Level, pVar, Gia_ObjFanin0(pVar), Gia_ObjFanin1(pVar) );
+    if ( Value0 == 1 || Value1 == 1 ) // one is 1 
+    {
+        if ( Value0 == 2 ) // first is unassigned
+            CbsP_ManAssign( p, Gia_Not(Gia_ObjChild0(pVar)), Level, pVar, Gia_ObjFanin1(pVar) );
+        if ( Value1 == 2 ) // second is unassigned
+            CbsP_ManAssign( p, Gia_Not(Gia_ObjChild1(pVar)), Level, pVar, Gia_ObjFanin0(pVar) );
+        return 0;
+    }
+    assert( CbsP_VarIsJust(pVar) );
+    assert( !CbsP_QueHasNode( &p->pJust, pVar ) );
+    CbsP_QuePush( &p->pJust, pVar );
+    return 0;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Propagates a variable.]
+
+  Description [Returns 1 if conflict; 0 if no conflict.]
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int CbsP_ManPropagateTwo( CbsP_Man_t * p, Gia_Obj_t * pVar, int Level )
+{
+    int Value0, Value1;
+    assert( !Gia_IsComplement(pVar) );
+    assert( Gia_ObjIsAnd(pVar) );
+    assert( CbsP_VarIsAssigned(pVar) );
+    assert( !CbsP_VarValue(pVar) );
+    Value0 = CbsP_VarFanin0Value(pVar);
+    Value1 = CbsP_VarFanin1Value(pVar);
+    // value is 0
+    if ( Value0 == 0 || Value1 == 0 ) // one is 0
+        return 0;
+    if ( Value0 == 1 && Value1 == 1 ) // both are 1
+        return CbsP_ManAnalyze( p, Level, pVar, Gia_ObjFanin0(pVar), Gia_ObjFanin1(pVar) );
+    assert( Value0 == 1 || Value1 == 1 );
+    if ( Value0 == 2 ) // first is unassigned
+        CbsP_ManAssign( p, Gia_Not(Gia_ObjChild0(pVar)), Level, pVar, Gia_ObjFanin1(pVar) );
+    if ( Value1 == 2 ) // first is unassigned
+        CbsP_ManAssign( p, Gia_Not(Gia_ObjChild1(pVar)), Level, pVar, Gia_ObjFanin0(pVar) );
+    return 0;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Propagates all variables.]
+
+  Description [Returns 1 if conflict; 0 if no conflict.]
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int CbsP_ManPropagate( CbsP_Man_t * p, int Level )
+{
+    int hClause;
+    Gia_Obj_t * pVar;
+    int i, k;
+    while ( 1 )
+    {
+        CbsP_QueForEachEntry( p->pProp, pVar, i )
+        {
+            if ( (hClause = CbsP_ManPropagateOne( p, pVar, Level )) )
+                return hClause;
+            if( CbsP_ManCheckPropLimits(p) )
+                return 0;
+        }
+        p->pProp.iHead = p->pProp.iTail;
+        k = p->pJust.iHead;
+        CbsP_QueForEachEntry( p->pJust, pVar, i )
+        {
+            if ( CbsP_VarIsJust( pVar ) )
+                p->pJust.pData[k++] = pVar;
+            else if ( (hClause = CbsP_ManPropagateTwo( p, pVar, Level )) )
+                return hClause;
+            if( CbsP_ManCheckPropLimits(p) )
+                return 0;
+        }
+        if ( k == p->pJust.iTail )
+            break;
+        p->pJust.iTail = k;
+    }
+    return 0;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Solve the problem recursively.]
+
+  Description [Returns learnt clause if unsat, NULL if sat or undecided.]
+               
+  SideEffects []
+
+  SeeAlso     []
+ 
+***********************************************************************/
+int CbsP_ManSolve_rec( CbsP_Man_t * p, int Level )
+{ 
+    CbsP_Que_t * pQue = &(p->pClauses);
+    Gia_Obj_t * pVar = NULL, * pDecVar;
+    int hClause, hLearn0, hLearn1;
+    int iPropHead, iJustHead, iJustTail;
+    // propagate assignments
+    assert( !CbsP_QueIsEmpty(&p->pProp) );
+    if ( (hClause = CbsP_ManPropagate( p, Level )) )
+        return hClause;
+    
+    // quit using resource limits
+    if ( CbsP_ManCheckLimits( p ) )
+        return 0;
+    // check for satisfying assignment
+    assert( CbsP_QueIsEmpty(&p->pProp) );
+    if ( CbsP_QueIsEmpty(&p->pJust) )
+        return 0;
+    p->Pars.nJustThis = Abc_MaxInt( p->Pars.nJustThis, p->pJust.iTail - p->pJust.iHead );
+    // remember the state before branching
+    iPropHead = p->pProp.iHead;
+    CbsP_QueStore( &p->pJust, &iJustHead, &iJustTail );
+    p->Pars.nJscanThis += iJustTail - iJustHead;
+    if ( CbsP_ManCheckLimits( p ) )
+        return 0;
+    // find the decision variable
+    if ( p->Pars.fUseHighest )
+        pVar = CbsP_ManDecideHighest( p );
+    else if ( p->Pars.fUseLowest )
+        pVar = CbsP_ManDecideLowest( p );
+    else if ( p->Pars.fUseMaxFF )
+        pVar = CbsP_ManDecideMaxFF( p );
+    else assert( 0 );
+    assert( CbsP_VarIsJust( pVar ) );
+    // chose decision variable using fanout count
+
+    if ( Gia_ObjRefNum(p->pAig, Gia_ObjFanin0(pVar)) > Gia_ObjRefNum(p->pAig, Gia_ObjFanin1(pVar)) )
+        pDecVar = Gia_Not(Gia_ObjChild0(pVar));
+    else
+        pDecVar = Gia_Not(Gia_ObjChild1(pVar));
+    
+//    pDecVar = Gia_NotCond( Gia_Regular(pDecVar), Gia_Regular(pDecVar)->fPhase );
+//    pDecVar = Gia_Not(pDecVar);
+    // decide on first fanin
+    CbsP_ManAssign( p, pDecVar, Level+1, NULL, NULL );
+    if ( !(hLearn0 = CbsP_ManSolve_rec( p, Level+1 )) )
+        return 0;
+    if ( CbsP_ManCheckLimits( p ) )
+        return 0;
+    if ( pQue->pData[hLearn0] != Gia_Regular(pDecVar) )
+        return hLearn0;
+    CbsP_ManCancelUntil( p, iPropHead );
+    CbsP_QueRestore( &p->pJust, iJustHead, iJustTail );
+    // decide on second fanin
+    CbsP_ManAssign( p, Gia_Not(pDecVar), Level+1, NULL, NULL );
+    if ( !(hLearn1 = CbsP_ManSolve_rec( p, Level+1 )) )
+        return 0;
+    if ( CbsP_ManCheckLimits( p ) )
+        return 0;
+    if ( pQue->pData[hLearn1] != Gia_Regular(pDecVar) )
+        return hLearn1;
+    hClause = CbsP_ManResolve( p, Level, hLearn0, hLearn1 );
+//    CbsP_ManPrintClauseNew( p, Level, hClause );
+//    if ( Level > CbsP_ClauseDecLevel(p, hClause) )
+//        p->Pars.nBTThisNc++;
+    p->Pars.nBTThis++;
+    return hClause;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Looking for a satisfying assignment of the node.]
+
+  Description [Assumes that each node has flag pObj->fMark0 set to 0.
+  Returns 1 if unsatisfiable, 0 if satisfiable, and -1 if undecided.
+  The node may be complemented. ]
+               
+  SideEffects [The two procedures differ in the CEX format.]
+
+  SeeAlso     []
+
+***********************************************************************/
+int CbsP_ManSolve( CbsP_Man_t * p, Gia_Obj_t * pObj )
+{
+    int RetValue = 0;
+//    s_Counter = 0;
+    assert( !p->pProp.iHead && !p->pProp.iTail );
+    assert( !p->pJust.iHead && !p->pJust.iTail );
+    assert( p->pClauses.iHead == 1 && p->pClauses.iTail == 1 );
+    p->Pars.nBTThis = p->Pars.nJustThis = p->Pars.nBTThisNc = 0;
+    CbsP_ManAssign( p, pObj, 0, NULL, NULL );
+    if ( !CbsP_ManSolve_rec(p, 0) && !CbsP_ManCheckLimits(p) )
+        CbsP_ManSaveModel( p, p->vModel );
+    else
+        RetValue = 1;
+    CbsP_ManCancelUntil( p, 0 );
+    p->pJust.iHead = p->pJust.iTail = 0;
+    p->pClauses.iHead = p->pClauses.iTail = 1;
+    p->Pars.nBTTotal += p->Pars.nBTThis;
+    p->Pars.nJustTotal = Abc_MaxInt( p->Pars.nJustTotal, p->Pars.nJustThis );
+    if ( CbsP_ManCheckLimits( p ) )
+        RetValue = -1;
+//    printf( "%d ", s_Counter );
+    return RetValue;
+}
+int CbsP_ManSolve2( CbsP_Man_t * p, Gia_Obj_t * pObj, Gia_Obj_t * pObj2 )
+{
+    abctime clk = Abc_Clock();
+    int RetValue = 0;
+//    s_Counter = 0;
+    assert( !p->pProp.iHead && !p->pProp.iTail );
+    assert( !p->pJust.iHead && !p->pJust.iTail );
+    assert( p->pClauses.iHead == 1 && p->pClauses.iTail == 1 );
+    p->Pars.nBTThis = p->Pars.nJustThis = p->Pars.nBTThisNc = 0;
+    p->Pars.nJscanThis = p->Pars.nRscanThis = p->Pars.nPropThis = 0;
+    CbsP_ManAssign( p, pObj, 0, NULL, NULL );
+    if ( pObj2 ) 
+    CbsP_ManAssign( p, pObj2, 0, NULL, NULL );
+    if ( !CbsP_ManSolve_rec(p, 0) && !CbsP_ManCheckLimits(p) )
+        CbsP_ManSaveModel( p, p->vModel );
+    else 
+        RetValue = 1;
+    CbsP_ManCancelUntil( p, 0 );
+
+    p->pJust.iHead = p->pJust.iTail = 0;
+    p->pClauses.iHead = p->pClauses.iTail = 1;
+    p->Pars.nBTTotal += p->Pars.nBTThis;
+    p->Pars.nJustTotal = Abc_MaxInt( p->Pars.nJustTotal, p->Pars.nJustThis );
+    if ( CbsP_ManCheckLimits( p ) )
+        RetValue = -1;
+
+    if( CBS_SAT == RetValue ){
+        p->nSatSat ++;
+        p->timeSatSat   += Abc_Clock() - clk;
+        p->nConfSat     += p->Pars.nBTThis;
+    } else
+    if( CBS_UNSAT == RetValue ){
+        p->nSatUnsat ++;
+        p->timeSatUnsat += Abc_Clock() - clk;
+        p->nConfUnsat   += p->Pars.nBTThis;
+    } else {
+        p->nSatUndec ++;
+        p->timeSatUndec += Abc_Clock() - clk;
+        p->nConfUndec   += p->Pars.nBTThis;
+    }
+//    printf( "%d ", s_Counter );
+    CbsP_UpdateRecord(&p->Pars,RetValue);
+    return RetValue;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Prints statistics of the manager.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void CbsP_ManSatPrintStats( CbsP_Man_t * p )
+{
+    printf( "CO = %8d  ", Gia_ManCoNum(p->pAig) );
+    printf( "AND = %8d  ", Gia_ManAndNum(p->pAig) );
+    printf( "Conf = %6d  ", p->Pars.nBTLimit );
+    printf( "JustMax = %5d  ", p->Pars.nJustLimit );
+    printf( "\n" );
+    printf( "Unsat calls %6d  (%6.2f %%)   Ave conf = %8.1f   ", 
+        p->nSatUnsat, p->nSatTotal? 100.0*p->nSatUnsat/p->nSatTotal :0.0, p->nSatUnsat? 1.0*p->nConfUnsat/p->nSatUnsat :0.0 );
+    ABC_PRTP( "Time", p->timeSatUnsat, p->timeTotal );
+    printf( "Sat   calls %6d  (%6.2f %%)   Ave conf = %8.1f   ", 
+        p->nSatSat,   p->nSatTotal? 100.0*p->nSatSat/p->nSatTotal :0.0, p->nSatSat? 1.0*p->nConfSat/p->nSatSat : 0.0 );
+    ABC_PRTP( "Time", p->timeSatSat,   p->timeTotal );
+    printf( "Undef calls %6d  (%6.2f %%)   Ave conf = %8.1f   ", 
+        p->nSatUndec, p->nSatTotal? 100.0*p->nSatUndec/p->nSatTotal :0.0, p->nSatUndec? 1.0*p->nConfUndec/p->nSatUndec : 0.0 );
+    ABC_PRTP( "Time", p->timeSatUndec, p->timeTotal );
+    ABC_PRT( "Total time", p->timeTotal );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Procedure to test the new SAT solver.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Vec_Int_t * CbsP_ManSolveMiterNc( Gia_Man_t * pAig, int nConfs, Vec_Str_t ** pvStatus, int f0Proved, int fVerbose )
+{
+    extern void Gia_ManCollectTest( Gia_Man_t * pAig );
+    extern void Cec_ManSatAddToStore( Vec_Int_t * vCexStore, Vec_Int_t * vCex, int Out );
+    CbsP_Man_t * p; 
+    Vec_Int_t * vCex, * vVisit, * vCexStore;
+    Vec_Str_t * vStatus;
+    Gia_Obj_t * pRoot; 
+    int i, status;
+    abctime clk, clkTotal = Abc_Clock();
+    assert( Gia_ManRegNum(pAig) == 0 );
+//    Gia_ManCollectTest( pAig );
+    // prepare AIG
+    Gia_ManCreateRefs( pAig );
+    Gia_ManCleanMark0( pAig );
+    Gia_ManCleanMark1( pAig );
+    Gia_ManFillValue( pAig ); // maps nodes into trail ids
+    Gia_ManSetPhase( pAig ); // maps nodes into trail ids
+    // create logic network
+    p = CbsP_ManAlloc( pAig );
+    p->Pars.nBTLimit = nConfs;
+    // create resulting data-structures
+    vStatus   = Vec_StrAlloc( Gia_ManPoNum(pAig) );
+    vCexStore = Vec_IntAlloc( 10000 );
+    vVisit    = Vec_IntAlloc( 100 );
+    vCex      = CbsP_ReadModel( p );
+    // solve for each output
+    Gia_ManForEachCo( pAig, pRoot, i )
+    {
+//        printf( "\n" );
+
+        Vec_IntClear( vCex );
+        if ( Gia_ObjIsConst0(Gia_ObjFanin0(pRoot)) )
+        {
+            if ( Gia_ObjFaninC0(pRoot) )
+            {
+//                printf( "Constant 1 output of SRM!!!\n" );
+                Cec_ManSatAddToStore( vCexStore, vCex, i ); // trivial counter-example
+                Vec_StrPush( vStatus, 0 );
+            }
+            else
+            {
+//                printf( "Constant 0 output of SRM!!!\n" );
+                Vec_StrPush( vStatus, 1 );
+            }
+            continue;
+        }
+        clk = Abc_Clock();
+        p->Pars.fUseHighest = 1;
+        p->Pars.fUseLowest  = 0;
+        status = CbsP_ManSolve( p, Gia_ObjChild0(pRoot) );
+//        printf( "\n" );
+/*
+        if ( status == -1 )
+        {
+            p->Pars.fUseHighest = 0;
+            p->Pars.fUseLowest  = 1;
+            status = CbsP_ManSolve( p, Gia_ObjChild0(pRoot) );
+        }
+*/
+        Vec_StrPush( vStatus, (char)status );
+        if ( status == -1 )
+        {
+            p->nSatUndec++;
+            p->nConfUndec += p->Pars.nBTThis;
+            Cec_ManSatAddToStore( vCexStore, NULL, i ); // timeout
+            p->timeSatUndec += Abc_Clock() - clk;
+            continue;
+        }
+        if ( status == 1 )
+        {
+            if ( f0Proved )
+                Gia_ManPatchCoDriver( pAig, i, 0 );
+            p->nSatUnsat++;
+            p->nConfUnsat += p->Pars.nBTThis;
+            p->timeSatUnsat += Abc_Clock() - clk;
+            continue;
+        }
+        p->nSatSat++;
+        p->nConfSat += p->Pars.nBTThis;
+//        Gia_SatVerifyPattern( pAig, pRoot, vCex, vVisit );
+        Cec_ManSatAddToStore( vCexStore, vCex, i );
+        p->timeSatSat += Abc_Clock() - clk;
+    }
+    Vec_IntFree( vVisit );
+    p->nSatTotal = Gia_ManPoNum(pAig);
+    p->timeTotal = Abc_Clock() - clkTotal;
+    if ( fVerbose )
+        CbsP_ManSatPrintStats( p );
+//    printf( "RecCalls = %8d.  RecClause = %8d.  RecNonChro = %8d.\n", p->nRecCall, p->nRecClause, p->nRecNonChro );
+    CbsP_ManStop( p );
+    *pvStatus = vStatus;
+
+//    printf( "Total number of cex literals = %d. (Ave = %d)\n", 
+//         Vec_IntSize(vCexStore)-2*p->nSatUndec-2*p->nSatSat, 
+//        (Vec_IntSize(vCexStore)-2*p->nSatUndec-2*p->nSatSat)/p->nSatSat );
+    return vCexStore;
+}
+
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+
+ABC_NAMESPACE_IMPL_END
+
diff --git a/src/aig/gia/giaCSatP.h b/src/aig/gia/giaCSatP.h
new file mode 100644
index 00000000..4182cd14
--- /dev/null
+++ b/src/aig/gia/giaCSatP.h
@@ -0,0 +1,117 @@
+#ifndef ABC__aig__gia__giaCSatP_h
+#define ABC__aig__gia__giaCSatP_h
+
+
+////////////////////////////////////////////////////////////////////////
+///                          INCLUDES                                ///
+////////////////////////////////////////////////////////////////////////
+
+#include "gia.h"
+
+////////////////////////////////////////////////////////////////////////
+///                         PARAMETERS                               ///
+////////////////////////////////////////////////////////////////////////
+
+
+ABC_NAMESPACE_HEADER_START
+
+
+typedef struct CbsP_Par_t_ CbsP_Par_t;
+struct CbsP_Par_t_
+{
+    // conflict limits
+    int           nBTLimit;     // limit on the number of conflicts
+    int           nJustLimit;   // limit on the size of justification queue
+    // current parameters
+    int           nBTThis;      // number of conflicts
+    int           nBTThisNc;    // number of conflicts
+    int           nJustThis;    // max size of the frontier
+    int           nBTTotal;     // total number of conflicts
+    int           nJustTotal;   // total size of the frontier
+    // decision heuristics
+    int           fUseHighest;  // use node with the highest ID
+    int           fUseLowest;   // use node with the highest ID
+    int           fUseMaxFF;    // use node with the largest fanin fanout
+    // other
+    int           fVerbose;
+    int           fUseProved;
+
+    // statistics 
+    int           nJscanThis;
+    int           nRscanThis;
+    int           nPropThis;
+    int           maxJscanUndec;
+    int           maxRscanUndec;
+    int           maxPropUndec;
+    int           maxJscanSolved;
+    int           maxRscanSolved;
+    int           maxPropSolved;
+    int nSat, nUnsat, nUndec;
+    long          accJscanSat;
+    long          accJscanUnsat;
+    long          accJscanUndec;
+    long          accRscanSat;
+    long          accRscanUnsat;
+    long          accRscanUndec;
+    long          accPropSat;
+    long          accPropUnsat;
+    long          accPropUndec;
+
+    // other limits 
+    int           nJscanLimit;
+    int           nRscanLimit;
+    int           nPropLimit;
+};
+
+typedef struct CbsP_Que_t_ CbsP_Que_t;
+struct CbsP_Que_t_
+{
+    int           iHead;        // beginning of the queue
+    int           iTail;        // end of the queue
+    int           nSize;        // allocated size
+    Gia_Obj_t **  pData;        // nodes stored in the queue
+};
+ 
+typedef struct CbsP_Man_t_ CbsP_Man_t;
+struct CbsP_Man_t_
+{
+    CbsP_Par_t     Pars;         // parameters
+    Gia_Man_t *   pAig;         // AIG manager
+    CbsP_Que_t     pProp;        // propagation queue
+    CbsP_Que_t     pJust;        // justification queue
+    CbsP_Que_t     pClauses;     // clause queue
+    Gia_Obj_t **  pIter;        // iterator through clause vars
+    Vec_Int_t *   vLevReas;     // levels and decisions
+    Vec_Int_t *   vValue;
+    Vec_Int_t *   vModel;       // satisfying assignment
+    Vec_Ptr_t *   vTemp;        // temporary storage
+    // SAT calls statistics
+    int           nSatUnsat;    // the number of proofs
+    int           nSatSat;      // the number of failure
+    int           nSatUndec;    // the number of timeouts
+    int           nSatTotal;    // the number of calls
+    // conflicts
+    int           nConfUnsat;   // conflicts in unsat problems
+    int           nConfSat;     // conflicts in sat problems
+    int           nConfUndec;   // conflicts in undec problems
+    // runtime stats
+    abctime       timeSatUnsat; // unsat
+    abctime       timeSatSat;   // sat
+    abctime       timeSatUndec; // undecided
+    abctime       timeTotal;    // total runtime
+};
+
+CbsP_Man_t * CbsP_ManAlloc( Gia_Man_t * pGia );
+void CbsP_ManStop( CbsP_Man_t * p );
+void CbsP_ManSatPrintStats( CbsP_Man_t * p );
+void CbsP_PrintRecord( CbsP_Par_t * pPars );
+int CbsP_ManSolve2( CbsP_Man_t * p, Gia_Obj_t * pObj, Gia_Obj_t * pObj2 );
+
+#define CBS_UNSAT  1
+#define CBS_SAT    0
+#define CBS_UNDEC -1
+
+ABC_NAMESPACE_HEADER_END
+
+
+#endif
diff --git a/src/aig/gia/module.make b/src/aig/gia/module.make
index d801a243..1cb7331c 100644
--- a/src/aig/gia/module.make
+++ b/src/aig/gia/module.make
@@ -15,6 +15,7 @@ SRC +=    src/aig/gia/giaAig.c \
     src/aig/gia/giaCSat.c \
     src/aig/gia/giaCSat2.c \
     src/aig/gia/giaCSat3.c \
+    src/aig/gia/giaCSatP.c \
     src/aig/gia/giaCTas.c \
     src/aig/gia/giaCut.c \
     src/aig/gia/giaDecs.c \
diff --git a/src/base/abci/abc.c b/src/base/abci/abc.c
index 9813fc1e..6f0f7a34 100644
--- a/src/base/abci/abc.c
+++ b/src/base/abci/abc.c
@@ -36996,11 +36996,12 @@ int Abc_CommandAbc9Fraig( Abc_Frame_t * pAbc, int argc, char ** argv )
     extern Gia_Man_t * Cec2_ManSimulateTest( Gia_Man_t * p, Cec_ParFra_t * pPars );
     extern Gia_Man_t * Cec3_ManSimulateTest( Gia_Man_t * p, Cec_ParFra_t * pPars );
     extern Gia_Man_t * Cec4_ManSimulateTest( Gia_Man_t * p, Cec_ParFra_t * pPars );
+    extern Gia_Man_t * Cec5_ManSimulateTest( Gia_Man_t * p, Cec_ParFra_t * pPars );
     Cec_ParFra_t ParsFra, * pPars = &ParsFra; Gia_Man_t * pTemp;
-    int c, fUseAlgo = 0, fUseAlgoG = 0, fUseAlgoG2 = 0;
+    int c, fUseAlgo = 0, fUseAlgoG = 0, fUseAlgoX = 0, fUseAlgoY = 0;
     Cec4_ManSetParams( pPars );
     Extra_UtilGetoptReset();
-    while ( ( c = Extra_UtilGetopt( argc, argv, "JWRILDCNPrmdckngxwvh" ) ) != EOF )
+    while ( ( c = Extra_UtilGetopt( argc, argv, "JWRILDCNPrmdckngxywvh" ) ) != EOF )
     {
         switch ( c )
         {
@@ -37125,7 +37126,10 @@ int Abc_CommandAbc9Fraig( Abc_Frame_t * pAbc, int argc, char ** argv )
             fUseAlgoG ^= 1;
             break;
         case 'x':
-            fUseAlgoG2 ^= 1;
+            fUseAlgoX ^= 1;
+            break;
+        case 'y':
+            fUseAlgoY ^= 1;
             break;
         case 'w':
             pPars->fVeryVerbose ^= 1;
@@ -37146,15 +37150,17 @@ int Abc_CommandAbc9Fraig( Abc_Frame_t * pAbc, int argc, char ** argv )
         pTemp = Cec2_ManSimulateTest( pAbc->pGia, pPars );
     else if ( fUseAlgoG )
         pTemp = Cec3_ManSimulateTest( pAbc->pGia, pPars );
-    else if ( fUseAlgoG2 )
+    else if ( fUseAlgoX )
         pTemp = Cec4_ManSimulateTest( pAbc->pGia, pPars );
+    else if ( fUseAlgoY )
+        pTemp = Cec5_ManSimulateTest( pAbc->pGia, pPars );
     else
         pTemp = Cec_ManSatSweeping( pAbc->pGia, pPars, 0 );
     Abc_FrameUpdateGia( pAbc, pTemp );
     return 0;
 
 usage:
-    Abc_Print( -2, "usage: &fraig [-JWRILDCNP <num>] [-rmdckngwvh]\n" );
+    Abc_Print( -2, "usage: &fraig [-JWRILDCNP <num>] [-rmdckngxywvh]\n" );
     Abc_Print( -2, "\t         performs combinational SAT sweeping\n" );
     Abc_Print( -2, "\t-J num : the solver type [default = %d]\n", pPars->jType );
     Abc_Print( -2, "\t-W num : the number of simulation words [default = %d]\n", pPars->nWords );
@@ -37172,6 +37178,8 @@ usage:
     Abc_Print( -2, "\t-k     : toggle using logic cones in the SAT solver [default = %s]\n", pPars->fUseCones? "yes": "no" );
     Abc_Print( -2, "\t-n     : toggle using new implementation [default = %s]\n", fUseAlgo? "yes": "no" );
     Abc_Print( -2, "\t-g     : toggle using another new implementation [default = %s]\n", fUseAlgoG? "yes": "no" );
+    Abc_Print( -2, "\t-x     : toggle using another new implementation [default = %s]\n", fUseAlgoX? "yes": "no" );
+    Abc_Print( -2, "\t-y     : toggle using another new implementation [default = %s]\n", fUseAlgoY? "yes": "no" );
     Abc_Print( -2, "\t-w     : toggle printing even more verbose information [default = %s]\n", pPars->fVeryVerbose? "yes": "no" );
     Abc_Print( -2, "\t-v     : toggle printing verbose information [default = %s]\n", pPars->fVerbose? "yes": "no" );
     Abc_Print( -2, "\t-h     : print the command usage\n");
diff --git a/src/proof/cec/cecSatG3.c b/src/proof/cec/cecSatG3.c
new file mode 100644
index 00000000..bdfa0f90
--- /dev/null
+++ b/src/proof/cec/cecSatG3.c
@@ -0,0 +1,2330 @@
+/**CFile****************************************************************
+
+  FileName    [cecSatG2.c]
+
+  SystemName  [ABC: Logic synthesis and verification system.]
+
+  PackageName [Combinational equivalence checking.]
+
+  Synopsis    [Detection of structural isomorphism.]
+
+  Author      [Alan Mishchenko]
+  
+  Affiliation [UC Berkeley]
+
+  Date        [Ver. 1.0. Started - June 20, 2005.]
+
+  Revision    [$Id: cecSatG2.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
+
+***********************************************************************/
+
+#include "aig/gia/gia.h"
+#include "misc/util/utilTruth.h"
+#include "cec.h"
+#include "aig/gia/giaCSatP.h"
+#include <stdlib.h>
+
+#define USE_GLUCOSE2
+
+#ifdef USE_GLUCOSE2
+
+#include "sat/glucose2/AbcGlucose2.h"
+
+#define sat_solver                         bmcg2_sat_solver
+#define sat_solver_start                   bmcg2_sat_solver_start
+#define sat_solver_stop                    bmcg2_sat_solver_stop
+#define sat_solver_addclause               bmcg2_sat_solver_addclause
+#define sat_solver_add_and                 bmcg2_sat_solver_add_and
+#define sat_solver_add_xor                 bmcg2_sat_solver_add_xor
+#define sat_solver_addvar                  bmcg2_sat_solver_addvar
+#define sat_solver_read_cex_varvalue       bmcg2_sat_solver_read_cex_varvalue
+#define sat_solver_reset                   bmcg2_sat_solver_reset
+#define sat_solver_set_conflict_budget     bmcg2_sat_solver_set_conflict_budget
+#define sat_solver_conflictnum             bmcg2_sat_solver_conflictnum
+#define sat_solver_solve                   bmcg2_sat_solver_solve
+#define sat_solver_read_cex_varvalue       bmcg2_sat_solver_read_cex_varvalue
+#define sat_solver_read_cex                bmcg2_sat_solver_read_cex
+#define sat_solver_jftr                    bmcg2_sat_solver_jftr
+#define sat_solver_set_jftr                bmcg2_sat_solver_set_jftr
+#define sat_solver_set_var_fanin_lit       bmcg2_sat_solver_set_var_fanin_lit
+#define sat_solver_start_new_round         bmcg2_sat_solver_start_new_round
+#define sat_solver_mark_cone               bmcg2_sat_solver_mark_cone
+
+#else
+
+#include "sat/glucose/AbcGlucose.h"
+
+#define sat_solver                         bmcg_sat_solver
+#define sat_solver_start                   bmcg_sat_solver_start
+#define sat_solver_stop                    bmcg_sat_solver_stop
+#define sat_solver_addclause               bmcg_sat_solver_addclause
+#define sat_solver_add_and                 bmcg_sat_solver_add_and
+#define sat_solver_add_xor                 bmcg_sat_solver_add_xor
+#define sat_solver_addvar                  bmcg_sat_solver_addvar
+#define sat_solver_read_cex_varvalue       bmcg_sat_solver_read_cex_varvalue
+#define sat_solver_reset                   bmcg_sat_solver_reset
+#define sat_solver_set_conflict_budget     bmcg_sat_solver_set_conflict_budget
+#define sat_solver_conflictnum             bmcg_sat_solver_conflictnum
+#define sat_solver_solve                   bmcg_sat_solver_solve
+#define sat_solver_read_cex_varvalue       bmcg_sat_solver_read_cex_varvalue
+#define sat_solver_read_cex                bmcg_sat_solver_read_cex
+#define sat_solver_jftr                    bmcg_sat_solver_jftr
+#define sat_solver_set_jftr                bmcg_sat_solver_set_jftr
+#define sat_solver_set_var_fanin_lit       bmcg_sat_solver_set_var_fanin_lit
+#define sat_solver_start_new_round         bmcg_sat_solver_start_new_round
+#define sat_solver_mark_cone               bmcg_sat_solver_mark_cone
+
+#endif
+
+ABC_NAMESPACE_IMPL_START
+
+
+////////////////////////////////////////////////////////////////////////
+///                        DECLARATIONS                              ///
+////////////////////////////////////////////////////////////////////////
+
+// SAT solving manager
+typedef struct Cec5_Man_t_ Cec5_Man_t;
+struct Cec5_Man_t_
+{
+    Cec_ParFra_t *   pPars;          // parameters
+    Gia_Man_t *      pAig;           // user's AIG
+    Gia_Man_t *      pNew;           // internal AIG
+    // SAT solving
+    sat_solver *     pSat;           // SAT solver
+    Vec_Ptr_t *      vFrontier;      // CNF construction
+    Vec_Ptr_t *      vFanins;        // CNF construction
+    Vec_Int_t *      vCexMin;        // minimized CEX
+    Vec_Int_t *      vClassUpdates;  // updated equiv classes
+    Vec_Int_t *      vCexStamps;     // time stamps
+    Vec_Int_t *      vCands;
+    Vec_Int_t *      vVisit;
+    Vec_Int_t *      vPat;
+    Vec_Int_t *      vDisprPairs;
+    Vec_Bit_t *      vFails;
+    Vec_Bit_t *      vCoDrivers;
+    int              iPosRead;       // candidate reading position
+    int              iPosWrite;      // candidate writing position
+    int              iLastConst;     // last const node proved
+    // refinement
+    Vec_Int_t *      vRefClasses;
+    Vec_Int_t *      vRefNodes;
+    Vec_Int_t *      vRefBins;
+    int *            pTable;
+    int              nTableSize;
+    // statistics
+    int              nItersSim;
+    int              nItersSat;
+    int              nAndNodes;
+    int              nPatterns;
+    int              nSatSat;
+    int              nSatUnsat;
+    int              nSatUndec;
+    int              nCallsSince;
+    int              nSimulates;
+    int              nRecycles;
+    int              nConflicts[3][3];
+    int              nGates[2];
+    int              nFaster[2];
+    abctime          timeCnf;
+    abctime          timeGenPats;
+    abctime          timeSatSat0;
+    abctime          timeSatUnsat0;
+    abctime          timeSatSat;
+    abctime          timeSatUnsat;
+    abctime          timeSatUndec;
+    abctime          timeSim;
+    abctime          timeRefine;
+    abctime          timeResimGlo;
+    abctime          timeResimLoc;
+    abctime          timeStart;
+
+    int              simTravId;
+    Vec_Int_t *      vPiPatsCache;
+    int              fEec;
+    int              LocalBatchSize;
+    Vec_Bit_t *      vCexSite;
+    int              simBound;
+    int              simStart;
+    int              approxLim;
+    int              simGlobalTop;
+    int              simBatchFactor;
+    int              adaRecycle;
+};
+
+static inline int    Cec5_ObjSatId( Gia_Man_t * p, Gia_Obj_t * pObj )             { return Gia_ObjCopy2Array(p, Gia_ObjId(p, pObj));                                                     }
+static inline int    Cec5_ObjSetSatId( Gia_Man_t * p, Gia_Obj_t * pObj, int Num ) { assert(Cec5_ObjSatId(p, pObj) == -1); Gia_ObjSetCopy2Array(p, Gia_ObjId(p, pObj), Num); Vec_IntPush(&p->vSuppVars, Gia_ObjId(p, pObj)); if ( Gia_ObjIsCi(pObj) ) Vec_IntPushTwo(&p->vCopiesTwo, Gia_ObjId(p, pObj), Num); assert(Vec_IntSize(&p->vVarMap) == Num); Vec_IntPush(&p->vVarMap, Gia_ObjId(p, pObj)); return Num;  }
+static inline void   Cec5_ObjCleanSatId( Gia_Man_t * p, Gia_Obj_t * pObj )        { assert(Cec5_ObjSatId(p, pObj) != -1); Gia_ObjSetCopy2Array(p, Gia_ObjId(p, pObj), -1);               }
+
+////////////////////////////////////////////////////////////////////////
+///                     FUNCTION DEFINITIONS                         ///
+////////////////////////////////////////////////////////////////////////
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Vec_Wrd_t * Cec5_EvalCombine( Vec_Int_t * vPats, int nPats, int nInputs, int nWords )
+{
+    //Vec_Wrd_t * vSimsPi = Vec_WrdStart( nInputs * nWords );
+    Vec_Wrd_t * vSimsPi = Vec_WrdStartRandom( nInputs * nWords );
+    int i, k, iLit, iPat = 0; word * pSim;
+    for ( i = 0; i < Vec_IntSize(vPats); i += Vec_IntEntry(vPats, i), iPat++ )
+        for ( k = 1; k < Vec_IntEntry(vPats, i)-1; k++ )
+            if ( (iLit = Vec_IntEntry(vPats, i+k)) )
+            {
+                assert( Abc_Lit2Var(iLit) > 0 && Abc_Lit2Var(iLit) <= nInputs );
+                pSim = Vec_WrdEntryP( vSimsPi, (Abc_Lit2Var(iLit)-1)*nWords );
+                if ( Abc_InfoHasBit( (unsigned*)pSim, iPat ) != Abc_LitIsCompl(iLit) )
+                    Abc_InfoXorBit( (unsigned*)pSim, iPat );
+            }
+    assert( iPat == nPats );
+    return vSimsPi;
+}
+void Cec5_EvalPatterns( Gia_Man_t * p, Vec_Int_t * vPats, int nPats )
+{
+    int nWords = Abc_Bit6WordNum(nPats);
+    Vec_Wrd_t * vSimsPi = Cec5_EvalCombine( vPats, nPats, Gia_ManCiNum(p), nWords );
+    Vec_Wrd_t * vSimsPo = Gia_ManSimPatSimOut( p, vSimsPi, 1 );
+    int i, Count = 0, nErrors = 0;
+    for ( i = 0; i < Gia_ManCoNum(p); i++ )
+    {
+        int CountThis = Abc_TtCountOnesVec( Vec_WrdEntryP(vSimsPo, i*nWords), nWords );
+        if ( CountThis == 0 )
+            continue;
+        printf( "%d ", CountThis );
+        nErrors += CountThis;
+        Count++;
+    }
+    printf( "\nDetected %d error POs with %d errors (average %.2f).\n", Count, nErrors, 1.0*nErrors/Abc_MaxInt(1, Count) );
+    Vec_WrdFree( vSimsPi );
+    Vec_WrdFree( vSimsPo );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Default parameter settings.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Cec5_ManSetParams( Cec_ParFra_t * pPars )
+{
+    memset( pPars, 0, sizeof(Cec_ParFra_t) );
+    pPars->jType          =       2;    // solver type
+    pPars->fSatSweeping   =       1;    // conflict limit at a node
+    pPars->nWords         =       4;    // simulation words
+    pPars->nRounds        =      10;    // simulation rounds
+    pPars->nItersMax      =    2000;    // this is a miter
+    pPars->nBTLimit       = 1000000;    // use logic cones
+    pPars->nBTLimitPo     =       0;    // use logic outputs
+    pPars->nSatVarMax     =    1000;    // the max number of SAT variables before recycling SAT solver
+    pPars->nCallsRecycle  =     500;    // calls to perform before recycling SAT solver
+    pPars->nGenIters      =     100;    // pattern generation iterations
+}
+
+/**Function*************************************************************
+
+  Synopsis    []
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+Cec5_Man_t * Cec5_ManCreate( Gia_Man_t * pAig, Cec_ParFra_t * pPars )
+{
+    Cec5_Man_t * p = ABC_CALLOC( Cec5_Man_t, 1 );
+    memset( p, 0, sizeof(Cec5_Man_t) );
+    p->timeStart     = Abc_Clock();
+    p->pPars         = pPars;
+    p->pAig          = pAig;
+    p->pSat          = sat_solver_start();  
+    sat_solver_set_jftr( p->pSat, pPars->jType );
+    p->vFrontier     = Vec_PtrAlloc( 1000 );
+    p->vFanins       = Vec_PtrAlloc( 100 );
+    p->vCexMin       = Vec_IntAlloc( 100 );
+    p->vClassUpdates = Vec_IntAlloc( 100 );
+    p->vCexStamps    = Vec_IntStart( Gia_ManObjNum(pAig) );
+    p->vCands        = Vec_IntAlloc( 100 );
+    p->vVisit        = Vec_IntAlloc( 100 );
+    p->vPat          = Vec_IntAlloc( 100 );
+    p->vDisprPairs   = Vec_IntAlloc( 100 );
+    p->vFails        = Vec_BitStart( Gia_ManObjNum(pAig) );
+    //pAig->pData     = p->pSat; // point AIG manager to the solver
+    //Vec_IntFreeP( &p->pAig->vPats );
+    //p->pAig->vPats = Vec_IntAlloc( 1000 );
+    p->simTravId     = 0;
+    p->vPiPatsCache  = Vec_IntAlloc( 100 );
+    p->fEec          = 0;
+    p->LocalBatchSize= 8;
+    p->vCexSite      = Vec_BitStart( Gia_ManObjNum(pAig) );
+    Vec_BitFill( p->vCexSite, Gia_ManObjNum(pAig), 0 );
+    p->simBound      = pPars->nWords;
+    p->simStart      = 0;
+    p->approxLim     = 600;
+    p->simBatchFactor= 1;
+    p->simGlobalTop  = 0;
+    p->adaRecycle    = 500;
+    if ( pPars->nBTLimitPo )
+    {
+        int i, Driver;
+        p->vCoDrivers = Vec_BitStart( Gia_ManObjNum(pAig) );
+        Gia_ManForEachCoDriverId( pAig, Driver, i )
+            Vec_BitWriteEntry( p->vCoDrivers, Driver, 1 );
+    }
+    return p;
+}
+void Cec5_ManDestroy( Cec5_Man_t * p )
+{
+    if ( p->pPars->fVerbose ) 
+    {
+        abctime timeTotal = Abc_Clock() - p->timeStart;
+        abctime timeSat   = p->timeSatSat0 + p->timeSatSat + p->timeSatUnsat0 + p->timeSatUnsat + p->timeSatUndec;
+        abctime timeOther = timeTotal - timeSat - p->timeSim - p->timeRefine - p->timeResimLoc - p->timeGenPats;// - p->timeResimGlo;
+        ABC_PRTP( "SAT solving  ", timeSat,          timeTotal );
+        ABC_PRTP( "  sat(easy)  ", p->timeSatSat0,   timeTotal );
+        ABC_PRTP( "  sat        ", p->timeSatSat,    timeTotal );
+        ABC_PRTP( "  unsat(easy)", p->timeSatUnsat0, timeTotal );
+        ABC_PRTP( "  unsat      ", p->timeSatUnsat,  timeTotal );
+        ABC_PRTP( "  fail       ", p->timeSatUndec,  timeTotal );
+        ABC_PRTP( "Generate CNF ", p->timeCnf,       timeTotal );
+        ABC_PRTP( "Generate pats", p->timeGenPats,   timeTotal );
+        ABC_PRTP( "Simulation   ", p->timeSim,       timeTotal );
+        ABC_PRTP( "Refinement   ", p->timeRefine,    timeTotal );
+        ABC_PRTP( "Resim global ", p->timeResimGlo,  timeTotal );
+        ABC_PRTP( "Resim local  ", p->timeResimLoc,  timeTotal );
+        ABC_PRTP( "Other        ", timeOther,        timeTotal );
+        ABC_PRTP( "TOTAL        ", timeTotal,        timeTotal );
+        fflush( stdout );
+    }
+    //printf( "Recorded %d patterns with %d literals (average %.2f).\n", 
+    //    p->pAig->nBitPats, Vec_IntSize(p->pAig->vPats) - 2*p->pAig->nBitPats, 1.0*Vec_IntSize(p->pAig->vPats)/Abc_MaxInt(1, p->pAig->nBitPats)-2 );
+    //Cec5_EvalPatterns( p->pAig, p->pAig->vPats, p->pAig->nBitPats );
+    //Vec_IntFreeP( &p->pAig->vPats );
+    Vec_WrdFreeP( &p->pAig->vSims );
+    Vec_WrdFreeP( &p->pAig->vSimsPi );
+    Gia_ManCleanMark01( p->pAig );
+    sat_solver_stop( p->pSat );
+    Gia_ManStopP( &p->pNew );
+    Vec_PtrFreeP( &p->vFrontier );
+    Vec_PtrFreeP( &p->vFanins );
+    Vec_IntFreeP( &p->vCexMin );
+    Vec_IntFreeP( &p->vClassUpdates );
+    Vec_IntFreeP( &p->vCexStamps );
+    Vec_IntFreeP( &p->vCands );
+    Vec_IntFreeP( &p->vVisit );
+    Vec_IntFreeP( &p->vPat );
+    Vec_IntFreeP( &p->vDisprPairs );
+    Vec_BitFreeP( &p->vFails );
+    Vec_BitFreeP( &p->vCoDrivers );
+    Vec_IntFreeP( &p->vRefClasses );
+    Vec_IntFreeP( &p->vRefNodes );
+    Vec_IntFreeP( &p->vRefBins );
+    Vec_IntFreeP( &p->vPiPatsCache );
+    Vec_BitFreeP( &p->vCexSite );
+    ABC_FREE( p->pTable );
+    ABC_FREE( p );
+}
+Gia_Man_t * Cec5_ManStartNew( Gia_Man_t * pAig )
+{
+    Gia_Obj_t * pObj; int i;
+    Gia_Man_t * pNew = Gia_ManStart( Gia_ManObjNum(pAig) );
+    pNew->pName = Abc_UtilStrsav( pAig->pName );
+    pNew->pSpec = Abc_UtilStrsav( pAig->pSpec );
+    if ( pAig->pMuxes )
+        pNew->pMuxes = ABC_CALLOC( unsigned, pNew->nObjsAlloc );
+    Gia_ManFillValue( pAig );
+    Gia_ManConst0(pAig)->Value = 0;
+    Gia_ManForEachCi( pAig, pObj, i )
+        pObj->Value = Gia_ManAppendCi( pNew );
+    Gia_ManHashAlloc( pNew );
+    Vec_IntFill( &pNew->vCopies2, Gia_ManObjNum(pAig), -1 );
+    Gia_ManSetRegNum( pNew, Gia_ManRegNum(pAig) );
+    return pNew;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Adds clauses to the solver.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Cec5_AddClausesMux( Gia_Man_t * p, Gia_Obj_t * pNode, sat_solver * pSat )
+{
+    int fPolarFlip = 0;
+    Gia_Obj_t * pNodeI, * pNodeT, * pNodeE;
+    int pLits[4], RetValue, VarF, VarI, VarT, VarE, fCompT, fCompE;
+
+    assert( !Gia_IsComplement( pNode ) );
+    assert( pNode->fMark0 );
+    // get nodes (I = if, T = then, E = else)
+    pNodeI = Gia_ObjRecognizeMux( pNode, &pNodeT, &pNodeE );
+    // get the variable numbers
+    VarF = Cec5_ObjSatId(p, pNode);
+    VarI = Cec5_ObjSatId(p, pNodeI);
+    VarT = Cec5_ObjSatId(p, Gia_Regular(pNodeT));
+    VarE = Cec5_ObjSatId(p, Gia_Regular(pNodeE));
+    // get the complementation flags
+    fCompT = Gia_IsComplement(pNodeT);
+    fCompE = Gia_IsComplement(pNodeE);
+
+    // f = ITE(i, t, e)
+
+    // i' + t' + f
+    // i' + t  + f'
+    // i  + e' + f
+    // i  + e  + f'
+
+    // create four clauses
+    pLits[0] = Abc_Var2Lit(VarI, 1);
+    pLits[1] = Abc_Var2Lit(VarT, 1^fCompT);
+    pLits[2] = Abc_Var2Lit(VarF, 0);
+    if ( fPolarFlip )
+    {
+        if ( pNodeI->fPhase )               pLits[0] = Abc_LitNot( pLits[0] );
+        if ( Gia_Regular(pNodeT)->fPhase )  pLits[1] = Abc_LitNot( pLits[1] );
+        if ( pNode->fPhase )                pLits[2] = Abc_LitNot( pLits[2] );
+    }
+    RetValue = sat_solver_addclause( pSat, pLits, 3 );
+    assert( RetValue );
+    pLits[0] = Abc_Var2Lit(VarI, 1);
+    pLits[1] = Abc_Var2Lit(VarT, 0^fCompT);
+    pLits[2] = Abc_Var2Lit(VarF, 1);
+    if ( fPolarFlip )
+    {
+        if ( pNodeI->fPhase )               pLits[0] = Abc_LitNot( pLits[0] );
+        if ( Gia_Regular(pNodeT)->fPhase )  pLits[1] = Abc_LitNot( pLits[1] );
+        if ( pNode->fPhase )                pLits[2] = Abc_LitNot( pLits[2] );
+    }
+    RetValue = sat_solver_addclause( pSat, pLits, 3 );
+    assert( RetValue );
+    pLits[0] = Abc_Var2Lit(VarI, 0);
+    pLits[1] = Abc_Var2Lit(VarE, 1^fCompE);
+    pLits[2] = Abc_Var2Lit(VarF, 0);
+    if ( fPolarFlip )
+    {
+        if ( pNodeI->fPhase )               pLits[0] = Abc_LitNot( pLits[0] );
+        if ( Gia_Regular(pNodeE)->fPhase )  pLits[1] = Abc_LitNot( pLits[1] );
+        if ( pNode->fPhase )                pLits[2] = Abc_LitNot( pLits[2] );
+    }
+    RetValue = sat_solver_addclause( pSat, pLits, 3 );
+    assert( RetValue );
+    pLits[0] = Abc_Var2Lit(VarI, 0);
+    pLits[1] = Abc_Var2Lit(VarE, 0^fCompE);
+    pLits[2] = Abc_Var2Lit(VarF, 1);
+    if ( fPolarFlip )
+    {
+        if ( pNodeI->fPhase )               pLits[0] = Abc_LitNot( pLits[0] );
+        if ( Gia_Regular(pNodeE)->fPhase )  pLits[1] = Abc_LitNot( pLits[1] );
+        if ( pNode->fPhase )                pLits[2] = Abc_LitNot( pLits[2] );
+    }
+    RetValue = sat_solver_addclause( pSat, pLits, 3 );
+    assert( RetValue );
+
+    // two additional clauses
+    // t' & e' -> f'
+    // t  & e  -> f 
+
+    // t  + e   + f'
+    // t' + e'  + f 
+
+    if ( VarT == VarE )
+    {
+//        assert( fCompT == !fCompE );
+        return;
+    }
+
+    pLits[0] = Abc_Var2Lit(VarT, 0^fCompT);
+    pLits[1] = Abc_Var2Lit(VarE, 0^fCompE);
+    pLits[2] = Abc_Var2Lit(VarF, 1);
+    if ( fPolarFlip )
+    {
+        if ( Gia_Regular(pNodeT)->fPhase )  pLits[0] = Abc_LitNot( pLits[0] );
+        if ( Gia_Regular(pNodeE)->fPhase )  pLits[1] = Abc_LitNot( pLits[1] );
+        if ( pNode->fPhase )                pLits[2] = Abc_LitNot( pLits[2] );
+    }
+    RetValue = sat_solver_addclause( pSat, pLits, 3 );
+    assert( RetValue );
+    pLits[0] = Abc_Var2Lit(VarT, 1^fCompT);
+    pLits[1] = Abc_Var2Lit(VarE, 1^fCompE);
+    pLits[2] = Abc_Var2Lit(VarF, 0);
+    if ( fPolarFlip )
+    {
+        if ( Gia_Regular(pNodeT)->fPhase )  pLits[0] = Abc_LitNot( pLits[0] );
+        if ( Gia_Regular(pNodeE)->fPhase )  pLits[1] = Abc_LitNot( pLits[1] );
+        if ( pNode->fPhase )                pLits[2] = Abc_LitNot( pLits[2] );
+    }
+    RetValue = sat_solver_addclause( pSat, pLits, 3 );
+    assert( RetValue );
+}
+void Cec5_AddClausesSuper( Gia_Man_t * p, Gia_Obj_t * pNode, Vec_Ptr_t * vSuper, sat_solver * pSat )
+{
+    int fPolarFlip = 0;
+    Gia_Obj_t * pFanin;
+    int * pLits, nLits, RetValue, i;
+    assert( !Gia_IsComplement(pNode) );
+    assert( Gia_ObjIsAnd( pNode ) );
+    // create storage for literals
+    nLits = Vec_PtrSize(vSuper) + 1;
+    pLits = ABC_ALLOC( int, nLits );
+    // suppose AND-gate is A & B = C
+    // add !A => !C   or   A + !C
+    Vec_PtrForEachEntry( Gia_Obj_t *, vSuper, pFanin, i )
+    {
+        pLits[0] = Abc_Var2Lit(Cec5_ObjSatId(p, Gia_Regular(pFanin)), Gia_IsComplement(pFanin));
+        pLits[1] = Abc_Var2Lit(Cec5_ObjSatId(p, pNode), 1);
+        if ( fPolarFlip )
+        {
+            if ( Gia_Regular(pFanin)->fPhase )  pLits[0] = Abc_LitNot( pLits[0] );
+            if ( pNode->fPhase )                pLits[1] = Abc_LitNot( pLits[1] );
+        }
+        RetValue = sat_solver_addclause( pSat, pLits, 2 );
+        assert( RetValue );
+    }
+    // add A & B => C   or   !A + !B + C
+    Vec_PtrForEachEntry( Gia_Obj_t *, vSuper, pFanin, i )
+    {
+        pLits[i] = Abc_Var2Lit(Cec5_ObjSatId(p, Gia_Regular(pFanin)), !Gia_IsComplement(pFanin));
+        if ( fPolarFlip )
+        {
+            if ( Gia_Regular(pFanin)->fPhase )  pLits[i] = Abc_LitNot( pLits[i] );
+        }
+    }
+    pLits[nLits-1] = Abc_Var2Lit(Cec5_ObjSatId(p, pNode), 0);
+    if ( fPolarFlip )
+    {
+        if ( pNode->fPhase )  pLits[nLits-1] = Abc_LitNot( pLits[nLits-1] );
+    }
+    RetValue = sat_solver_addclause( pSat, pLits, nLits );
+    assert( RetValue );
+    ABC_FREE( pLits );
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Adds clauses and returns CNF variable of the node.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Cec5_CollectSuper_rec( Gia_Obj_t * pObj, Vec_Ptr_t * vSuper, int fFirst, int fUseMuxes )
+{
+    // if the new node is complemented or a PI, another gate begins
+    if ( Gia_IsComplement(pObj) || Gia_ObjIsCi(pObj) || 
+         (!fFirst && Gia_ObjValue(pObj) > 1) || 
+         (fUseMuxes && pObj->fMark0) )
+    {
+        Vec_PtrPushUnique( vSuper, pObj );
+        return;
+    }
+    // go through the branches
+    Cec5_CollectSuper_rec( Gia_ObjChild0(pObj), vSuper, 0, fUseMuxes );
+    Cec5_CollectSuper_rec( Gia_ObjChild1(pObj), vSuper, 0, fUseMuxes );
+}
+void Cec5_CollectSuper( Gia_Obj_t * pObj, int fUseMuxes, Vec_Ptr_t * vSuper )
+{
+    assert( !Gia_IsComplement(pObj) );
+    assert( !Gia_ObjIsCi(pObj) );
+    Vec_PtrClear( vSuper );
+    Cec5_CollectSuper_rec( pObj, vSuper, 1, fUseMuxes );
+}
+void Cec5_ObjAddToFrontier( Gia_Man_t * p, Gia_Obj_t * pObj, Vec_Ptr_t * vFrontier, sat_solver * pSat )
+{
+    assert( !Gia_IsComplement(pObj) );
+    assert( !Gia_ObjIsConst0(pObj) );
+    if ( Cec5_ObjSatId(p, pObj) >= 0 )
+        return;
+    assert( Cec5_ObjSatId(p, pObj) == -1 );
+    Cec5_ObjSetSatId( p, pObj, sat_solver_addvar(pSat) );
+    if ( Gia_ObjIsAnd(pObj) )
+        Vec_PtrPush( vFrontier, pObj );
+}
+int Cec5_ObjGetCnfVar( Cec5_Man_t * p, int iObj )
+{ 
+    int fUseSimple = 1; // enable simple CNF
+    int fUseMuxes  = 1; // enable MUXes when using complex CNF
+    Gia_Obj_t * pNode, * pFanin;
+    Gia_Obj_t * pObj = Gia_ManObj(p->pNew, iObj);
+    int i, k;
+    // quit if CNF is ready
+    if ( Cec5_ObjSatId(p->pNew,pObj) >= 0 )
+        return Cec5_ObjSatId(p->pNew,pObj);
+
+    assert( iObj > 0 );
+    if ( Gia_ObjIsCi(pObj) )
+        return Cec5_ObjSetSatId( p->pNew, pObj, sat_solver_addvar(p->pSat) );
+    assert( Gia_ObjIsAnd(pObj) );
+    if ( fUseSimple )
+    {
+        Gia_Obj_t * pFan0, * pFan1;
+        //if ( Gia_ObjRecognizeExor(pObj, &pFan0, &pFan1) )
+        //    printf( "%d", (Gia_IsComplement(pFan1) << 1) + Gia_IsComplement(pFan0) );
+        if ( p->pNew->pMuxes == NULL && Gia_ObjRecognizeExor(pObj, &pFan0, &pFan1) && Gia_IsComplement(pFan0) == Gia_IsComplement(pFan1) )
+        {
+            int iVar0 = Cec5_ObjGetCnfVar( p, Gia_ObjId(p->pNew, Gia_Regular(pFan0)) );
+            int iVar1 = Cec5_ObjGetCnfVar( p, Gia_ObjId(p->pNew, Gia_Regular(pFan1)) );
+            int iVar  = Cec5_ObjSetSatId( p->pNew, pObj, sat_solver_addvar(p->pSat) );
+            if ( p->pPars->jType < 2 )
+                sat_solver_add_xor( p->pSat, iVar, iVar0, iVar1, 0 );
+            if ( p->pPars->jType > 0 )
+            {
+                int Lit0 = Abc_Var2Lit( iVar0, 0 );
+                int Lit1 = Abc_Var2Lit( iVar1, 0 );
+                if ( Lit0 < Lit1 )
+                     Lit1 ^= Lit0, Lit0 ^= Lit1, Lit1 ^= Lit0;
+                assert( Lit0 > Lit1 );
+                sat_solver_set_var_fanin_lit( p->pSat, iVar, Lit0, Lit1 );
+                p->nGates[1]++;
+            }
+        }
+        else
+        {
+            int iVar0 = Cec5_ObjGetCnfVar( p, Gia_ObjFaninId0(pObj, iObj) );
+            int iVar1 = Cec5_ObjGetCnfVar( p, Gia_ObjFaninId1(pObj, iObj) );
+            int iVar  = Cec5_ObjSetSatId( p->pNew, pObj, sat_solver_addvar(p->pSat) );
+            if ( p->pPars->jType < 2 )
+            {
+                if ( Gia_ObjIsXor(pObj) )
+                    sat_solver_add_xor( p->pSat, iVar, iVar0, iVar1, Gia_ObjFaninC0(pObj) ^ Gia_ObjFaninC1(pObj) );
+                else
+                    sat_solver_add_and( p->pSat, iVar, iVar0, iVar1, Gia_ObjFaninC0(pObj), Gia_ObjFaninC1(pObj), 0 );
+            }
+            if ( p->pPars->jType > 0 )
+            {
+                int Lit0 = Abc_Var2Lit( iVar0, Gia_ObjFaninC0(pObj) );
+                int Lit1 = Abc_Var2Lit( iVar1, Gia_ObjFaninC1(pObj) );
+                if ( (Lit0 > Lit1) ^ Gia_ObjIsXor(pObj) )
+                     Lit1 ^= Lit0, Lit0 ^= Lit1, Lit1 ^= Lit0;
+                sat_solver_set_var_fanin_lit( p->pSat, iVar, Lit0, Lit1 );
+                p->nGates[Gia_ObjIsXor(pObj)]++;
+            }
+        }
+        return Cec5_ObjSatId( p->pNew, pObj );
+    }
+    assert( !Gia_ObjIsXor(pObj) );
+    // start the frontier
+    Vec_PtrClear( p->vFrontier );
+    Cec5_ObjAddToFrontier( p->pNew, pObj, p->vFrontier, p->pSat );
+    // explore nodes in the frontier
+    Vec_PtrForEachEntry( Gia_Obj_t *, p->vFrontier, pNode, i )
+    {
+        // create the supergate
+        assert( Cec5_ObjSatId(p->pNew,pNode) >= 0 );
+        if ( fUseMuxes && pNode->fMark0 )
+        {
+            Vec_PtrClear( p->vFanins );
+            Vec_PtrPushUnique( p->vFanins, Gia_ObjFanin0( Gia_ObjFanin0(pNode) ) );
+            Vec_PtrPushUnique( p->vFanins, Gia_ObjFanin0( Gia_ObjFanin1(pNode) ) );
+            Vec_PtrPushUnique( p->vFanins, Gia_ObjFanin1( Gia_ObjFanin0(pNode) ) );
+            Vec_PtrPushUnique( p->vFanins, Gia_ObjFanin1( Gia_ObjFanin1(pNode) ) );
+            Vec_PtrForEachEntry( Gia_Obj_t *, p->vFanins, pFanin, k )
+                Cec5_ObjAddToFrontier( p->pNew, Gia_Regular(pFanin), p->vFrontier, p->pSat );
+            Cec5_AddClausesMux( p->pNew, pNode, p->pSat );
+        }
+        else
+        {
+            Cec5_CollectSuper( pNode, fUseMuxes, p->vFanins );
+            Vec_PtrForEachEntry( Gia_Obj_t *, p->vFanins, pFanin, k )
+                Cec5_ObjAddToFrontier( p->pNew, Gia_Regular(pFanin), p->vFrontier, p->pSat );
+            Cec5_AddClausesSuper( p->pNew, pNode, p->vFanins, p->pSat );
+        }
+        assert( Vec_PtrSize(p->vFanins) > 1 );
+    }
+    return Cec5_ObjSatId(p->pNew,pObj);
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Refinement of equivalence classes.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline word * Cec5_ObjSim( Gia_Man_t * p, int iObj )
+{
+    return Vec_WrdEntryP( p->vSims, p->nSimWords * iObj );
+}
+static inline int Cec5_ObjSimEqual( Gia_Man_t * p, int iObj0, int iObj1 )
+{
+    int w;
+    word * pSim0 = Cec5_ObjSim( p, iObj0 );
+    word * pSim1 = Cec5_ObjSim( p, iObj1 );
+    if ( (pSim0[0] & 1) == (pSim1[0] & 1) )
+    {
+        for ( w = 0; w < p->nSimWords; w++ )
+            if ( pSim0[w] != pSim1[w] )
+                return 0;
+        return 1;
+    }
+    else
+    {
+        for ( w = 0; w < p->nSimWords; w++ )
+            if ( pSim0[w] != ~pSim1[w] )
+                return 0;
+        return 1;
+    }
+}
+int Cec5_ManSimHashKey( word * pSim, int nSims, int nTableSize )
+{
+    static int s_Primes[16] = { 
+        1291, 1699, 1999, 2357, 2953, 3313, 3907, 4177, 
+        4831, 5147, 5647, 6343, 6899, 7103, 7873, 8147 };
+    unsigned uHash = 0, * pSimU = (unsigned *)pSim;
+    int i, nSimsU = 2 * nSims;
+    if ( pSimU[0] & 1 )
+        for ( i = 0; i < nSimsU; i++ )
+            uHash ^= ~pSimU[i] * s_Primes[i & 0xf];
+    else
+        for ( i = 0; i < nSimsU; i++ )
+            uHash ^= pSimU[i] * s_Primes[i & 0xf];
+    return (int)(uHash % nTableSize);
+
+}
+void Cec5_RefineOneClassIter( Gia_Man_t * p, int iRepr )
+{
+    int iObj, iPrev = iRepr, iPrev2, iRepr2;
+    assert( Gia_ObjRepr(p, iRepr) == GIA_VOID );
+    assert( Gia_ObjNext(p, iRepr) > 0 );
+    Gia_ClassForEachObj1( p, iRepr, iRepr2 )
+        if ( Cec5_ObjSimEqual(p, iRepr, iRepr2) )
+            iPrev = iRepr2;
+        else
+            break;
+    if ( iRepr2 <= 0 ) // no refinement
+        return;
+    // relink remaining nodes of the class
+    // nodes that are equal to iRepr, remain in the class of iRepr
+    // nodes that are not equal to iRepr, move to the class of iRepr2
+    Gia_ObjSetRepr( p, iRepr2, GIA_VOID );
+    assert( !Gia_ObjProved(p,iRepr2) );
+    iPrev2 = iRepr2;
+    for ( iObj = Gia_ObjNext(p, iRepr2); iObj > 0; iObj = Gia_ObjNext(p, iObj) )
+    {
+        if ( Cec5_ObjSimEqual(p, iRepr, iObj) ) // remains with iRepr
+        {
+            Gia_ObjSetNext( p, iPrev, iObj );
+            iPrev = iObj;
+        }
+        else // moves to iRepr2
+        {
+            Gia_ObjSetRepr( p, iObj, iRepr2 );
+            Gia_ObjSetNext( p, iPrev2, iObj );
+            iPrev2 = iObj;
+        }
+    }
+    Gia_ObjSetNext( p, iPrev, -1 );
+    Gia_ObjSetNext( p, iPrev2, -1 );
+    // refine incrementally
+    if ( Gia_ObjNext(p, iRepr2) > 0 )
+        Cec5_RefineOneClassIter( p, iRepr2 );
+}
+void Cec5_RefineOneClass( Gia_Man_t * p, Cec5_Man_t * pMan, Vec_Int_t * vNodes )
+{
+    int k, iObj, Bin;
+    Vec_IntClear( pMan->vRefBins );
+    Vec_IntForEachEntryReverse( vNodes, iObj, k )
+    {
+        int Key = Cec5_ManSimHashKey( Cec5_ObjSim(p, iObj), p->nSimWords, pMan->nTableSize );
+        assert( Key >= 0 && Key < pMan->nTableSize );
+        if ( pMan->pTable[Key] == -1 )
+            Vec_IntPush( pMan->vRefBins, Key );
+        p->pNexts[iObj] = pMan->pTable[Key];
+        pMan->pTable[Key] = iObj;
+    }
+    Vec_IntForEachEntry( pMan->vRefBins, Bin, k )
+    {
+        int iRepr = pMan->pTable[Bin];
+        pMan->pTable[Bin] = -1;
+        assert( p->pReprs[iRepr].iRepr == GIA_VOID );
+        assert( p->pNexts[iRepr] != 0 );
+        assert( !Gia_ObjProved(p,iRepr) );
+        if ( p->pNexts[iRepr] == -1 )
+            continue;
+        for ( iObj = p->pNexts[iRepr]; iObj > 0; iObj = p->pNexts[iObj] )
+            p->pReprs[iObj].iRepr = iRepr;
+        Cec5_RefineOneClassIter( p, iRepr );
+    }
+    Vec_IntClear( pMan->vRefBins );
+}
+void Cec5_RefineClasses( Gia_Man_t * p, Cec5_Man_t * pMan, Vec_Int_t * vClasses )
+{
+    if ( Vec_IntSize(pMan->vRefClasses) == 0 )
+        return;
+    if ( Vec_IntSize(pMan->vRefNodes) > 0 )
+        Cec5_RefineOneClass( p, pMan, pMan->vRefNodes );
+    else
+    {
+        int i, k, iObj, iRepr;
+        Vec_IntForEachEntry( pMan->vRefClasses, iRepr, i )
+        {
+            assert( p->pReprs[iRepr].fColorA );
+            p->pReprs[iRepr].fColorA = 0;
+            Vec_IntClear( pMan->vRefNodes );
+            Vec_IntPush( pMan->vRefNodes, iRepr );
+            Gia_ClassForEachObj1( p, iRepr, k )
+                Vec_IntPush( pMan->vRefNodes, k );
+            Vec_IntForEachEntry( pMan->vRefNodes, iObj, k )
+            {
+                p->pReprs[iObj].iRepr = GIA_VOID;
+                p->pNexts[iObj] = -1;
+            }
+            Cec5_RefineOneClass( p, pMan, pMan->vRefNodes );
+        }
+    }
+    Vec_IntClear( pMan->vRefClasses );
+    Vec_IntClear( pMan->vRefNodes );
+}
+void Cec5_RefineInit( Gia_Man_t * p, Cec5_Man_t * pMan )
+{
+    Gia_Obj_t * pObj; int i;
+    if( pMan->fEec ){
+        assert( p->pReprs );
+        assert( p->pNexts );
+    } else {
+        ABC_FREE( p->pReprs );
+        ABC_FREE( p->pNexts );
+        p->pReprs = ABC_CALLOC( Gia_Rpr_t, Gia_ManObjNum(p) );
+        p->pNexts = ABC_FALLOC( int, Gia_ManObjNum(p) );
+    }
+
+    pMan->nTableSize  = Abc_PrimeCudd( Gia_ManObjNum(p) );
+    pMan->pTable      = ABC_FALLOC( int, pMan->nTableSize );
+    pMan->vRefNodes   = Vec_IntAlloc( Gia_ManObjNum(p) );
+    
+    pMan->vRefBins    = Vec_IntAlloc( Gia_ManObjNum(p)/2 );
+    pMan->vRefClasses = Vec_IntAlloc( Gia_ManObjNum(p)/2 );
+
+    if( pMan->fEec ) return;
+
+    Gia_ManForEachObj( p, pObj, i )
+    {
+        p->pReprs[i].iRepr = GIA_VOID;
+        if ( !Gia_ObjIsCo(pObj) && (!pMan->pPars->nLevelMax || Gia_ObjLevel(p, pObj) <= pMan->pPars->nLevelMax) )
+            Vec_IntPush( pMan->vRefNodes, i );
+    }
+    
+    Vec_IntPush( pMan->vRefClasses, 0 );
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Internal simulation APIs.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline void Cec5_ObjSimSetInputBit( Gia_Man_t * p, int iObj, int Bit )
+{
+    word * pSim = Cec5_ObjSim( p, iObj );
+    if ( Abc_InfoHasBit( (unsigned*)pSim, p->iPatsPi ) != Bit )
+        Abc_InfoXorBit( (unsigned*)pSim, p->iPatsPi );
+}
+static inline int Cec5_ObjSimGetInputBit( Gia_Man_t * p, int iObj )
+{
+    word * pSim = Cec5_ObjSim( p, iObj );
+    return Abc_InfoHasBit( (unsigned*)pSim, p->iPatsPi );
+}
+static inline void Cec5_ObjSimRo( Gia_Man_t * p, int iObj )
+{
+    int w;
+    word * pSimRo = Cec5_ObjSim( p, iObj );
+    word * pSimRi = Cec5_ObjSim( p, Gia_ObjRoToRiId(p, iObj) );
+    for ( w = 0; w < p->nSimWords; w++ )
+        pSimRo[w] = pSimRi[w];
+}
+static inline void Cec5_ObjSimCo( Gia_Man_t * p, int iObj )
+{
+    int w;
+    Gia_Obj_t * pObj = Gia_ManObj( p, iObj );
+    word * pSimCo  = Cec5_ObjSim( p, iObj );
+    word * pSimDri = Cec5_ObjSim( p, Gia_ObjFaninId0(pObj, iObj) );
+    if ( Gia_ObjFaninC0(pObj) )
+        for ( w = 0; w < p->nSimWords; w++ )
+            pSimCo[w] = ~pSimDri[w];
+    else
+        for ( w = 0; w < p->nSimWords; w++ )
+            pSimCo[w] =  pSimDri[w];
+}
+static inline void Cec5_ObjSimAnd( Gia_Man_t * p, Cec5_Man_t * pMan, int iObj )
+{
+    int w;
+    Gia_Obj_t * pObj = Gia_ManObj( p, iObj );
+    word * pSim  = Cec5_ObjSim( p, iObj );
+    word * pSim0 = Cec5_ObjSim( p, Gia_ObjFaninId0(pObj, iObj) );
+    word * pSim1 = Cec5_ObjSim( p, Gia_ObjFaninId1(pObj, iObj) );
+    if ( Gia_ObjFaninC0(pObj) && Gia_ObjFaninC1(pObj) )
+        for ( w = pMan->simStart; w < pMan->simBound; w++ )
+            pSim[w] = ~pSim0[w] & ~pSim1[w];
+    else if ( Gia_ObjFaninC0(pObj) && !Gia_ObjFaninC1(pObj) )
+        for ( w = pMan->simStart; w < pMan->simBound; w++ )
+            pSim[w] = ~pSim0[w] & pSim1[w];
+    else if ( !Gia_ObjFaninC0(pObj) && Gia_ObjFaninC1(pObj) )
+        for ( w = pMan->simStart; w < pMan->simBound; w++ )
+            pSim[w] = pSim0[w] & ~pSim1[w];
+    else
+        for ( w = pMan->simStart; w < pMan->simBound; w++ )
+            pSim[w] = pSim0[w] & pSim1[w];
+}
+static inline void Cec5_ObjSimXor( Gia_Man_t * p, Cec5_Man_t * pMan, int iObj )
+{
+    int w;
+    Gia_Obj_t * pObj = Gia_ManObj( p, iObj );
+    word * pSim  = Cec5_ObjSim( p, iObj );
+    word * pSim0 = Cec5_ObjSim( p, Gia_ObjFaninId0(pObj, iObj) );
+    word * pSim1 = Cec5_ObjSim( p, Gia_ObjFaninId1(pObj, iObj) );
+    if ( Gia_ObjFaninC0(pObj) ^ Gia_ObjFaninC1(pObj) )
+        for ( w = pMan->simStart; w < pMan->simBound; w++ )
+            pSim[w] = ~pSim0[w] ^ pSim1[w];
+    else
+        for ( w = pMan->simStart; w < pMan->simBound; w++ )
+            pSim[w] =  pSim0[w] ^ pSim1[w];
+}
+static inline void Cec5_ObjSimCi( Gia_Man_t * p, int iObj )
+{
+    int w;
+    word * pSim = Cec5_ObjSim( p, iObj );
+    for ( w = 0; w < p->nSimWords; w++ )
+        pSim[w] = Gia_ManRandomW( 0 );
+    pSim[0] <<= 1;
+}
+static inline void Cec5_ObjClearSimCi( Gia_Man_t * p, int iObj )
+{
+    int w;
+    word * pSim = Cec5_ObjSim( p, iObj );
+    for ( w = 0; w < p->nSimWords; w++ )
+        pSim[w] = 0;
+}
+void Cec5_ManSimulateCis( Gia_Man_t * p )
+{
+    int i, Id;
+    Gia_ManForEachCiId( p, Id, i )
+        Cec5_ObjSimCi( p, Id );
+    p->iPatsPi = 0;
+}
+void Cec5_ManClearCis( Gia_Man_t * p )
+{
+    int i, Id;
+    Gia_ManForEachCiId( p, Id, i )
+        Cec5_ObjClearSimCi( p, Id );
+    p->iPatsPi = 0;
+}
+Abc_Cex_t * Cec5_ManDeriveCex( Gia_Man_t * p, int iOut, int iPat )
+{
+    Abc_Cex_t * pCex;
+    int i, Id;
+    pCex = Abc_CexAlloc( 0, Gia_ManCiNum(p), 1 );
+    pCex->iPo = iOut;
+    if ( iPat == -1 )
+        return pCex;
+    Gia_ManForEachCiId( p, Id, i )
+        if ( Abc_InfoHasBit((unsigned *)Cec5_ObjSim(p, Id), iPat) )
+            Abc_InfoSetBit( pCex->pData, i );
+    return pCex;
+}
+int Cec5_ManSimulateCos( Gia_Man_t * p )
+{
+    int i, Id;
+    // check outputs and generate CEX if they fail
+    Gia_ManForEachCoId( p, Id, i )
+    {
+        Cec5_ObjSimCo( p, Id );
+        if ( Cec5_ObjSimEqual(p, Id, 0) )
+            continue;
+        p->pCexSeq = Cec5_ManDeriveCex( p, i, Abc_TtFindFirstBit2(Cec5_ObjSim(p, Id), p->nSimWords) );
+        return 0;
+    }
+    return 1;
+}
+void Cec5_ManSimulate( Gia_Man_t * p, Cec5_Man_t * pMan )
+{
+    abctime clk = Abc_Clock();
+    Gia_Obj_t * pObj; int i;
+    pMan->nSimulates++;
+    if ( pMan->pTable == NULL )
+        Cec5_RefineInit( p, pMan );
+    else
+        assert( Vec_IntSize(pMan->vRefClasses) == 0 );
+
+    pMan->simStart = pMan->simGlobalTop;
+    Gia_ManForEachAnd( p, pObj, i )
+    {
+        int iRepr = Gia_ObjRepr( p, i );
+        if ( Gia_ObjIsXor(pObj) )
+            Cec5_ObjSimXor( p, pMan, i );
+        else
+            Cec5_ObjSimAnd( p, pMan, i );
+        if ( iRepr == GIA_VOID || p->pReprs[iRepr].fColorA || Cec5_ObjSimEqual(p, iRepr, i) )
+            continue;
+        p->pReprs[iRepr].fColorA = 1;
+        Vec_IntPush( pMan->vRefClasses, iRepr );
+    }
+    pMan->simStart = 0;
+    pMan->timeSim += Abc_Clock() - clk;
+    clk = Abc_Clock();
+    Cec5_RefineClasses( p, pMan, pMan->vRefClasses );
+    pMan->timeRefine += Abc_Clock() - clk;
+}
+void Cec5_ManSimulate_rec( Gia_Man_t * p, Cec5_Man_t * pMan, int iObj )
+{
+    Gia_Obj_t * pObj; 
+    int progress;
+    if ( !iObj || (progress = Vec_IntEntry(pMan->vCexStamps, iObj)) == pMan->simTravId )
+        return;
+    Vec_IntWriteEntry( pMan->vCexStamps, iObj, pMan->simTravId );
+    pObj = Gia_ManObj(p, iObj);
+    if ( Gia_ObjIsCi(pObj) )
+        return;
+    assert( Gia_ObjIsAnd(pObj) );
+    Cec5_ManSimulate_rec( p, pMan, Gia_ObjFaninId0(pObj, iObj) );
+    Cec5_ManSimulate_rec( p, pMan, Gia_ObjFaninId1(pObj, iObj) );
+    pMan->simStart = progress * pMan->LocalBatchSize / (sizeof(word)<<3);
+    if ( Gia_ObjIsXor(pObj) )
+        Cec5_ObjSimXor( p, pMan, iObj );
+    else
+        Cec5_ObjSimAnd( p, pMan, iObj );
+    pMan->simStart = 0;
+}
+void Cec5_ManSimAlloc( Gia_Man_t * p, int nWords, int fPrep )
+{
+    if( !fPrep ){
+        Vec_WrdFreeP( &p->vSimsPi );
+        p->vSimsPi   = Vec_WrdStart( (Gia_ManCiNum(p) + 1) * nWords );
+    }
+    Vec_WrdFreeP( &p->vSims );
+    p->vSims     = Vec_WrdStart( Gia_ManObjNum(p) * nWords );
+    p->nSimWords = nWords;
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Creating initial equivalence classes.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Cec5_ManPrintTfiConeStats( Gia_Man_t * p )
+{
+    Vec_Int_t * vRoots  = Vec_IntAlloc( 100 );
+    Vec_Int_t * vNodes  = Vec_IntAlloc( 100 );
+    Vec_Int_t * vLeaves = Vec_IntAlloc( 100 );
+    int i, k;
+    Gia_ManForEachClass0( p, i )
+    {
+        Vec_IntClear( vRoots );
+        if ( i % 100 != 0 )
+            continue;
+        Vec_IntPush( vRoots, i );
+        Gia_ClassForEachObj1( p, i, k )
+            Vec_IntPush( vRoots, k );
+        Gia_ManCollectTfi( p, vRoots, vNodes );
+        printf( "Class %6d : ", i );
+        printf( "Roots = %6d  ", Vec_IntSize(vRoots) );
+        printf( "Nodes = %6d  ", Vec_IntSize(vNodes) );
+        printf( "\n" );
+    }
+    Vec_IntFree( vRoots );
+    Vec_IntFree( vNodes );
+    Vec_IntFree( vLeaves );
+}
+void Cec5_ManPrintStats( Gia_Man_t * p, Cec_ParFra_t * pPars, Cec5_Man_t * pMan, int fSim )
+{
+    static abctime clk = 0;
+    abctime clkThis = 0;
+    int i, nLits, Counter = 0, Counter0 = 0, CounterX = 0;
+    if ( !pPars->fVerbose )
+        return;
+    if ( pMan->nItersSim + pMan->nItersSat )
+        clkThis = Abc_Clock() - clk;
+    clk = Abc_Clock();
+    for ( i = 0; i < Gia_ManObjNum(p); i++ )
+    {
+        if ( Gia_ObjIsHead(p, i) )
+            Counter++;
+        else if ( Gia_ObjIsConst(p, i) )
+            Counter0++;
+        else if ( Gia_ObjIsNone(p, i) )
+            CounterX++;
+    }
+    nLits = Gia_ManObjNum(p) - Counter - CounterX;
+    if ( fSim )
+    {
+        printf( "Sim %4d : ",     pMan->nItersSim++ + pMan->nItersSat );
+        printf( "%6.2f %%  ", 100.0*nLits/Gia_ManCandNum(p) );
+    }
+    else
+    {
+        printf( "SAT %4d : ",     pMan->nItersSim + pMan->nItersSat++ );
+        printf( "%6.2f %%  ", 100.0*pMan->nAndNodes/Gia_ManAndNum(p) );
+    }
+    printf( "P =%7d  ",   pMan ? pMan->nSatUnsat : 0 );
+    printf( "D =%7d  ",   pMan ? pMan->nSatSat   : 0 );
+    printf( "F =%8d  ",   pMan ? pMan->nSatUndec : 0 );
+    //printf( "Last =%6d  ", pMan ? pMan->iLastConst : 0 );
+    Abc_Print( 1, "cst =%9d  cls =%8d  lit =%9d   ",  Counter0, Counter, nLits );
+    Abc_PrintTime( 1, "Time", clkThis );
+}
+void Cec5_ManPrintClasses2( Gia_Man_t * p )
+{
+    int i, k;
+    Gia_ManForEachClass0( p, i )
+    {
+        printf( "Class %d : ", i );
+        Gia_ClassForEachObj1( p, i, k )
+            printf( "%d ", k );
+        printf( "\n" );
+    }
+}
+void Cec5_ManPrintClasses( Gia_Man_t * p )
+{
+    int k, Count = 0;
+    Gia_ClassForEachObj1( p, 0, k )
+        Count++;
+    printf( "Const0 class has %d entries.\n", Count );
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Verify counter-example.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Cec5_ManVerify_rec( Gia_Man_t * p, int iObj, sat_solver * pSat )
+{
+    int Value0, Value1;
+    Gia_Obj_t * pObj = Gia_ManObj( p, iObj );
+    if ( iObj == 0 ) return 0;
+    if ( Gia_ObjIsTravIdCurrentId(p, iObj) )
+        return pObj->fMark1;
+    Gia_ObjSetTravIdCurrentId(p, iObj);
+    if ( Gia_ObjIsCi(pObj) )
+        return pObj->fMark1 = sat_solver_read_cex_varvalue(pSat, Cec5_ObjSatId(p, pObj));
+    assert( Gia_ObjIsAnd(pObj) );
+    Value0 = Cec5_ManVerify_rec( p, Gia_ObjFaninId0(pObj, iObj), pSat ) ^ Gia_ObjFaninC0(pObj);
+    Value1 = Cec5_ManVerify_rec( p, Gia_ObjFaninId1(pObj, iObj), pSat ) ^ Gia_ObjFaninC1(pObj);
+    return pObj->fMark1 = Gia_ObjIsXor(pObj) ? Value0 ^ Value1 : Value0 & Value1;
+}
+void Cec5_ManVerify( Gia_Man_t * p, int iObj0, int iObj1, int fPhase, sat_solver * pSat )
+{
+    int Value0, Value1;
+    Gia_ManIncrementTravId( p );
+    Value0 = Cec5_ManVerify_rec( p, iObj0, pSat );
+    Value1 = Cec5_ManVerify_rec( p, iObj1, pSat );
+    if ( (Value0 ^ Value1) == fPhase )
+        printf( "CEX verification FAILED for obj %d and obj %d.\n", iObj0, iObj1 );
+//    else
+//        printf( "CEX verification succeeded for obj %d and obj %d.\n", iObj0, iObj1 );;
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Verify counter-example.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+int Cec5_ManCexVerify_rec( Gia_Man_t * p, int iObj )
+{
+    int Value0, Value1;
+    Gia_Obj_t * pObj = Gia_ManObj( p, iObj );
+    if ( iObj == 0 ) return 0;
+    if ( Gia_ObjIsTravIdCurrentId(p, iObj) )
+        return pObj->fMark1;
+    Gia_ObjSetTravIdCurrentId(p, iObj);
+    if ( Gia_ObjIsCi(pObj) )
+        return pObj->fMark1 = Cec5_ObjSimGetInputBit(p, iObj);
+    assert( Gia_ObjIsAnd(pObj) );
+    Value0 = Cec5_ManCexVerify_rec( p, Gia_ObjFaninId0(pObj, iObj) ) ^ Gia_ObjFaninC0(pObj);
+    Value1 = Cec5_ManCexVerify_rec( p, Gia_ObjFaninId1(pObj, iObj) ) ^ Gia_ObjFaninC1(pObj);
+    return pObj->fMark1 = Gia_ObjIsXor(pObj) ? Value0 ^ Value1 : Value0 & Value1;
+}
+void Cec5_ManCexVerify( Gia_Man_t * p, int iObj0, int iObj1, int fPhase )
+{
+    int Value0, Value1;
+    Gia_ManIncrementTravId( p );
+    Value0 = Cec5_ManCexVerify_rec( p, iObj0 );
+    Value1 = Cec5_ManCexVerify_rec( p, iObj1 );
+    if ( (Value0 ^ Value1) == fPhase )
+        printf( "CEX verification FAILED for obj %d and obj %d.\n", iObj0, iObj1 );
+//    else
+//        printf( "CEX verification succeeded for obj %d and obj %d.\n", iObj0, iObj1 );;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Packs simulation patterns into array of simulation info.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+*************************************`**********************************/
+void Cec5_ManPackAddPatterns( Gia_Man_t * p, int iBit, Vec_Int_t * vLits )
+{
+    int k, Limit = Abc_MinInt( Vec_IntSize(vLits), 64 * p->nSimWords - 1 );
+    for ( k = 0; k < Limit; k++ )
+    {
+        int i, Lit, iBitLocal = (iBit + k + 1) % Limit + 1;
+        assert( iBitLocal > 0 && iBitLocal < 64 * p->nSimWords );
+        Vec_IntForEachEntry( vLits, Lit, i )
+        {
+            word * pInfo = Vec_WrdEntryP( p->vSims,   p->nSimWords * Abc_Lit2Var(Lit) );
+            word * pPres = Vec_WrdEntryP( p->vSimsPi, p->nSimWords * Abc_Lit2Var(Lit) );
+            if ( Abc_InfoHasBit( (unsigned *)pPres, iBitLocal ) )
+                continue;
+            if ( Abc_InfoHasBit( (unsigned *)pInfo, iBitLocal ) != Abc_LitIsCompl(Lit ^ (i == k)) )
+                 Abc_InfoXorBit( (unsigned *)pInfo, iBitLocal );
+        }
+    }
+}
+int Cec5_ManPackAddPatternTry( Gia_Man_t * p, int iBit, Vec_Int_t * vLits )
+{
+    int i, Lit;
+    assert( p->iPatsPi > 0 && p->iPatsPi < 64 * p->nSimWords );
+    Vec_IntForEachEntry( vLits, Lit, i )
+    {
+        word * pInfo = Vec_WrdEntryP( p->vSims,   p->nSimWords * Abc_Lit2Var(Lit) );
+        word * pPres = Vec_WrdEntryP( p->vSimsPi, p->nSimWords * Abc_Lit2Var(Lit) );
+        if ( Abc_InfoHasBit( (unsigned *)pPres, iBit ) && 
+             Abc_InfoHasBit( (unsigned *)pInfo, iBit ) != Abc_LitIsCompl(Lit) )
+             return 0;
+    }
+    Vec_IntForEachEntry( vLits, Lit, i )
+    {
+        word * pInfo = Vec_WrdEntryP( p->vSims,   p->nSimWords * Abc_Lit2Var(Lit) );
+        word * pPres = Vec_WrdEntryP( p->vSimsPi, p->nSimWords * Abc_Lit2Var(Lit) );
+        Abc_InfoSetBit( (unsigned *)pPres, iBit );
+        if ( Abc_InfoHasBit( (unsigned *)pInfo, iBit ) != Abc_LitIsCompl(Lit) )
+             Abc_InfoXorBit( (unsigned *)pInfo, iBit );
+    }
+    return 1;
+}
+int Cec5_ManPackAddPattern( Gia_Man_t * p, Vec_Int_t * vLits, int fExtend )
+{
+    int k;
+    for ( k = 1; k < 64 * p->nSimWords - 1; k++ )
+    {
+        if ( ++p->iPatsPi == 64 * p->nSimWords - 1 )
+            p->iPatsPi = 1;
+        if ( Cec5_ManPackAddPatternTry( p, p->iPatsPi, vLits ) )
+        {
+            if ( fExtend )
+                Cec5_ManPackAddPatterns( p, p->iPatsPi, vLits );
+            break;
+        }
+    }
+    if ( k == 64 * p->nSimWords - 1 )
+    {
+        p->iPatsPi = k;
+        if ( !Cec5_ManPackAddPatternTry( p, p->iPatsPi, vLits ) )
+            printf( "Internal error.\n" );
+        else if ( fExtend )
+            Cec5_ManPackAddPatterns( p, p->iPatsPi, vLits );
+        return 64 * p->nSimWords;
+    }
+    return k;
+}
+
+/**Function*************************************************************
+
+  Synopsis    [Generates counter-examples to refine the candidate equivalences.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+static inline int Cec5_ObjFan0IsAssigned( Gia_Obj_t * pObj )
+{
+    return Gia_ObjFanin0(pObj)->fMark0 || Gia_ObjFanin0(pObj)->fMark1;
+}
+static inline int Cec5_ObjFan1IsAssigned( Gia_Obj_t * pObj )
+{
+    return Gia_ObjFanin1(pObj)->fMark0 || Gia_ObjFanin1(pObj)->fMark1;
+}
+static inline int Cec5_ObjFan0HasValue( Gia_Obj_t * pObj, int v )
+{
+    return (v ^ Gia_ObjFaninC0(pObj)) ? Gia_ObjFanin0(pObj)->fMark1 : Gia_ObjFanin0(pObj)->fMark0;
+}
+static inline int Cec5_ObjFan1HasValue( Gia_Obj_t * pObj, int v )
+{
+    return (v ^ Gia_ObjFaninC1(pObj)) ? Gia_ObjFanin1(pObj)->fMark1 : Gia_ObjFanin1(pObj)->fMark0;
+}
+static inline int Cec5_ObjObjIsImpliedValue( Gia_Obj_t * pObj, int v )
+{
+    assert( !pObj->fMark0 && !pObj->fMark1 ); // not visited
+    if ( v ) 
+    return Cec5_ObjFan0HasValue(pObj, 1) && Cec5_ObjFan1HasValue(pObj, 1);
+    return Cec5_ObjFan0HasValue(pObj, 0) || Cec5_ObjFan1HasValue(pObj, 0);
+}
+static inline int Cec5_ObjFan0IsImpliedValue( Gia_Obj_t * pObj, int v )
+{
+    return Gia_ObjIsAnd(Gia_ObjFanin0(pObj)) && Cec5_ObjObjIsImpliedValue( Gia_ObjFanin0(pObj), v ^ Gia_ObjFaninC0(pObj) );
+}
+static inline int Cec5_ObjFan1IsImpliedValue( Gia_Obj_t * pObj, int v )
+{
+    return Gia_ObjIsAnd(Gia_ObjFanin1(pObj)) && Cec5_ObjObjIsImpliedValue( Gia_ObjFanin1(pObj), v ^ Gia_ObjFaninC1(pObj) );
+}
+int Cec5_ManGeneratePatterns_rec( Gia_Man_t * p, Gia_Obj_t * pObj, int Value, Vec_Int_t * vPat, Vec_Int_t * vVisit )
+{
+    Gia_Obj_t * pFan0, * pFan1;
+    assert( !pObj->fMark0 && !pObj->fMark1 ); // not visited
+    if ( Value ) pObj->fMark1 = 1; else pObj->fMark0 = 1;
+    Vec_IntPush( vVisit, Gia_ObjId(p, pObj) );
+    if ( Gia_ObjIsCi(pObj) )
+    {
+        Vec_IntPush( vPat, Abc_Var2Lit(Gia_ObjId(p, pObj), Value) );
+        return 1;
+    }
+    assert( Gia_ObjIsAnd(pObj) );
+    pFan0 = Gia_ObjFanin0(pObj);
+    pFan1 = Gia_ObjFanin1(pObj);
+    if ( Gia_ObjIsXor(pObj) )
+    {
+        int Ass0 = Cec5_ObjFan0IsAssigned(pObj);
+        int Ass1 = Cec5_ObjFan1IsAssigned(pObj);
+        assert( Gia_ObjFaninC0(pObj) == 0 && Gia_ObjFaninC1(pObj) == 0 );
+        if ( Ass0 && Ass1 )
+            return Value == (Cec5_ObjFan0HasValue(pObj, 1) ^ Cec5_ObjFan1HasValue(pObj, 1));
+        if ( Ass0 )
+        {
+            int ValueInt = Value ^ Cec5_ObjFan0HasValue(pObj, 1);
+            if ( !Cec5_ManGeneratePatterns_rec(p, pFan1, ValueInt, vPat, vVisit) )
+                return 0;
+        }
+        else if ( Ass1 )
+        {
+            int ValueInt = Value ^ Cec5_ObjFan1HasValue(pObj, 1);
+            if ( !Cec5_ManGeneratePatterns_rec(p, pFan0, ValueInt, vPat, vVisit) )
+                return 0;
+        }
+        else if ( Abc_Random(0) & 1 )
+        {
+            if ( !Cec5_ManGeneratePatterns_rec(p, pFan0, 0,      vPat, vVisit) )
+                return 0;
+            if ( Cec5_ObjFan1HasValue(pObj, !Value) || (!Cec5_ObjFan1HasValue(pObj, Value) && !Cec5_ManGeneratePatterns_rec(p, pFan1, Value,  vPat, vVisit)) )
+                return 0;
+        }
+        else
+        {
+            if ( !Cec5_ManGeneratePatterns_rec(p, pFan0, 1,      vPat, vVisit) )
+                return 0;
+            if ( Cec5_ObjFan1HasValue(pObj, Value) || (!Cec5_ObjFan1HasValue(pObj, !Value) && !Cec5_ManGeneratePatterns_rec(p, pFan1, !Value, vPat, vVisit)) )
+                return 0;
+        }
+        assert( Value == (Cec5_ObjFan0HasValue(pObj, 1) ^ Cec5_ObjFan1HasValue(pObj, 1)) );
+        return 1;
+    }
+    else if ( Value )
+    {
+        if ( Cec5_ObjFan0HasValue(pObj, 0) || Cec5_ObjFan1HasValue(pObj, 0) )
+            return 0;
+        if ( !Cec5_ObjFan0HasValue(pObj, 1) && !Cec5_ManGeneratePatterns_rec(p, pFan0, !Gia_ObjFaninC0(pObj), vPat, vVisit) )
+            return 0;
+        if ( !Cec5_ObjFan1HasValue(pObj, 1) && !Cec5_ManGeneratePatterns_rec(p, pFan1, !Gia_ObjFaninC1(pObj), vPat, vVisit) )
+            return 0;
+        assert( Cec5_ObjFan0HasValue(pObj, 1) && Cec5_ObjFan1HasValue(pObj, 1) );
+        return 1;
+    }
+    else
+    {
+        if ( Cec5_ObjFan0HasValue(pObj, 1) && Cec5_ObjFan1HasValue(pObj, 1) )
+            return 0;
+        if ( Cec5_ObjFan0HasValue(pObj, 0) || Cec5_ObjFan1HasValue(pObj, 0) )
+            return 1;
+        if ( Cec5_ObjFan0HasValue(pObj, 1) )
+        {
+            if ( !Cec5_ManGeneratePatterns_rec(p, pFan1, Gia_ObjFaninC1(pObj), vPat, vVisit) )
+                return 0;
+        }
+        else if ( Cec5_ObjFan1HasValue(pObj, 1) )
+        {
+            if ( !Cec5_ManGeneratePatterns_rec(p, pFan0, Gia_ObjFaninC0(pObj), vPat, vVisit) )
+                return 0;
+        }
+        else
+        {
+            if ( Cec5_ObjFan0IsImpliedValue( pObj, 0 ) )
+            {
+                if ( !Cec5_ManGeneratePatterns_rec(p, pFan0, Gia_ObjFaninC0(pObj), vPat, vVisit) )
+                    return 0;
+            }
+            else if ( Cec5_ObjFan1IsImpliedValue( pObj, 0 ) )
+            {
+                if ( !Cec5_ManGeneratePatterns_rec(p, pFan1, Gia_ObjFaninC1(pObj), vPat, vVisit) )
+                    return 0;
+            }
+            else if ( Cec5_ObjFan0IsImpliedValue( pObj, 1 ) )
+            {
+                if ( !Cec5_ManGeneratePatterns_rec(p, pFan1, Gia_ObjFaninC1(pObj), vPat, vVisit) )
+                    return 0;
+            }
+            else if ( Cec5_ObjFan1IsImpliedValue( pObj, 1 ) )
+            {
+                if ( !Cec5_ManGeneratePatterns_rec(p, pFan0, Gia_ObjFaninC0(pObj), vPat, vVisit) )
+                    return 0;
+            }
+            else if ( Abc_Random(0) & 1 )
+            {
+                if ( !Cec5_ManGeneratePatterns_rec(p, pFan1, Gia_ObjFaninC1(pObj), vPat, vVisit) )
+                    return 0;
+            }
+            else
+            {
+                if ( !Cec5_ManGeneratePatterns_rec(p, pFan0, Gia_ObjFaninC0(pObj), vPat, vVisit) )
+                    return 0;
+            }
+        }
+        assert( Cec5_ObjFan0HasValue(pObj, 0) || Cec5_ObjFan1HasValue(pObj, 0) );
+        return 1;
+    }
+}
+int Cec5_ManGeneratePatternOne( Gia_Man_t * p, int iRepr, int iReprVal, int iCand, int iCandVal, Vec_Int_t * vPat, Vec_Int_t * vVisit )
+{
+    int Res, k;
+    Gia_Obj_t * pObj;
+    assert( iCand > 0 );
+    if ( !iRepr && iReprVal )
+        return 0;
+    Vec_IntClear( vPat );
+    Vec_IntClear( vVisit );
+    //Gia_ManForEachObj( p, pObj, k )
+    //    assert( !pObj->fMark0 && !pObj->fMark1 );
+    Res = (!iRepr || Cec5_ManGeneratePatterns_rec(p, Gia_ManObj(p, iRepr), iReprVal, vPat, vVisit)) && Cec5_ManGeneratePatterns_rec(p, Gia_ManObj(p, iCand), iCandVal, vPat, vVisit);
+    Gia_ManForEachObjVec( vVisit, p, pObj, k )
+        pObj->fMark0 = pObj->fMark1 = 0;
+    return Res;
+}
+void Cec5_ManCandIterStart( Cec5_Man_t * p )
+{
+    int i, * pArray;
+    assert( p->iPosWrite == 0 );
+    assert( p->iPosRead == 0 );
+    assert( Vec_IntSize(p->vCands) == 0 );
+    for ( i = 1; i < Gia_ManObjNum(p->pAig); i++ )
+        if ( Gia_ObjRepr(p->pAig, i) != GIA_VOID )
+            Vec_IntPush( p->vCands, i );
+    pArray = Vec_IntArray( p->vCands );
+    for ( i = 0; i < Vec_IntSize(p->vCands); i++ )
+    {
+        int iNew = Abc_Random(0) % Vec_IntSize(p->vCands);
+        ABC_SWAP( int, pArray[i], pArray[iNew] );
+    }
+}
+int Cec5_ManCandIterNext( Cec5_Man_t * p )
+{
+    while ( Vec_IntSize(p->vCands) > 0 )
+    {
+        int fStop, iCand = Vec_IntEntry( p->vCands, p->iPosRead );
+        if ( (fStop = (Gia_ObjRepr(p->pAig, iCand) != GIA_VOID)) )
+            Vec_IntWriteEntry( p->vCands, p->iPosWrite++, iCand );
+        if ( ++p->iPosRead == Vec_IntSize(p->vCands) )
+        {
+            Vec_IntShrink( p->vCands, p->iPosWrite );
+            p->iPosWrite = 0;
+            p->iPosRead = 0;
+        }
+        if ( fStop )
+            return iCand;
+    }
+    return 0;
+}
+int Cec5_ManGeneratePatterns( Cec5_Man_t * p )
+{
+    abctime clk = Abc_Clock();
+    int i, iCand, nPats = 100 * 64 * p->pAig->nSimWords, CountPat = 0, Packs = 0;
+    //int iRepr;
+    //Vec_IntForEachEntryDouble( p->vDisprPairs, iRepr, iCand, i )
+    //    if ( iRepr == Gia_ObjRepr(p->pAig, iCand) )
+    //        printf( "Pair %6d (%6d, %6d) (new repr = %9d) is FAILED to disprove.\n", i, iRepr, iCand, Gia_ObjRepr(p->pAig, iCand) );
+    //    else
+    //        printf( "Pair %6d (%6d, %6d) (new repr = %9d) is disproved.\n", i, iRepr, iCand, Gia_ObjRepr(p->pAig, iCand) );
+    //Vec_IntClear( p->vDisprPairs );
+    p->pAig->iPatsPi = 0;
+    Vec_WrdFill( p->pAig->vSimsPi, Vec_WrdSize(p->pAig->vSimsPi), 0 );
+    for ( i = 0; i < nPats; i++ )
+        if ( (iCand = Cec5_ManCandIterNext(p)) )
+        {
+            int iRepr    = Gia_ObjRepr( p->pAig, iCand );
+            int iCandVal = Gia_ManObj(p->pAig, iCand)->fPhase;
+            int iReprVal = Gia_ManObj(p->pAig, iRepr)->fPhase;
+            int Res = Cec5_ManGeneratePatternOne( p->pAig, iRepr,  iReprVal, iCand, !iCandVal, p->vPat, p->vVisit );
+            if ( !Res )
+                Res = Cec5_ManGeneratePatternOne( p->pAig, iRepr, !iReprVal, iCand,  iCandVal, p->vPat, p->vVisit );
+            if ( Res )
+            {
+                int Ret = Cec5_ManPackAddPattern( p->pAig, p->vPat, 1 );
+                if ( p->pAig->vPats )
+                {
+                    Vec_IntPush( p->pAig->vPats, Vec_IntSize(p->vPat)+2 );
+                    Vec_IntAppend( p->pAig->vPats, p->vPat );
+                    Vec_IntPush( p->pAig->vPats, -1 );
+                }
+                //Vec_IntPushTwo( p->vDisprPairs, iRepr, iCand );
+                Packs += Ret;
+                if ( 0 == (Ret % (64 * p->pAig->nSimWords / p->simBatchFactor)) )
+                    break;
+                if ( ++CountPat == 8 * 64 * p->pAig->nSimWords )
+                    break;
+                //Cec5_ManCexVerify( p->pAig, iRepr, iCand, iReprVal ^ iCandVal );
+                //Gia_ManCleanMark01( p->pAig );
+            }
+        }
+    p->timeGenPats += Abc_Clock() - clk;
+    p->nSatSat += CountPat;
+    //printf( "%3d : %6.2f %% : Generated %6d CEXs after trying %6d pairs.  Ave packs = %9.2f  Ave tries = %9.2f  (Limit = %9.2f)\n", 
+    //    p->nItersSim++, 100.0*Vec_IntSize(p->vCands)/Gia_ManAndNum(p->pAig),
+    //    CountPat, i, (float)Packs / Abc_MaxInt(1, CountPat), (float)i / Abc_MaxInt(1, CountPat), (float)nPats / p->pPars->nItersMax );
+    return CountPat >= i / p->pPars->nItersMax;
+}
+
+
+/**Function*************************************************************
+
+  Synopsis    [Internal simulation APIs.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+void Cec5_ManSatSolverRecycle( Cec5_Man_t * p )
+{
+    Gia_Obj_t * pObj;
+    int i;
+    //printf( "Solver size = %d.\n", sat_solver_varnum(p->pSat) );
+    if( p->adaRecycle && p->adaRecycle < p->nConflicts[2][2] )
+        return;
+    p->nRecycles++;
+    p->nCallsSince = 0;
+    sat_solver_reset( p->pSat );
+    // clean mapping of AigIds into SatIds
+    Gia_ManForEachObjVec( &p->pNew->vSuppVars, p->pNew, pObj, i )
+        Cec5_ObjCleanSatId( p->pNew, pObj );
+    Vec_IntClear( &p->pNew->vSuppVars  );  // AigIds for which SatId is defined
+    Vec_IntClear( &p->pNew->vCopiesTwo );  // pairs (CiAigId, SatId)
+    Vec_IntClear( &p->pNew->vVarMap    );  // mapping of SatId into AigId
+}
+void Cec5_ManLoadInstance( Cec5_Man_t * p, int iObj0, int iObj1, int * piVar0, int * piVar1 ){
+    int iVar0 = Cec5_ObjGetCnfVar( p, iObj0 );
+    int iVar1 = Cec5_ObjGetCnfVar( p, iObj1 );
+    if( p->pPars->jType > 0 )
+    {
+        extern void glucose2_markapprox( void * pSat, int v0, int v1, int nlim );
+        int nlim = p->approxLim;
+        glucose2_markapprox( p->pSat, iVar0, iVar1, nlim );
+    }
+
+    * piVar0 = iVar0;
+    * piVar1 = iVar1;
+}
+
+int Cec5_ManSolveTwo( Cec5_Man_t * p, int iObj0, int iObj1, int fPhase, int * pfEasy, int fVerbose, int fEffort )
+{
+    abctime clk;
+    int nBTLimit = fEffort ? p->pPars->nBTLimitPo : (Vec_BitEntry(p->vFails, iObj0) || Vec_BitEntry(p->vFails, iObj1)) ? Abc_MaxInt(1, p->pPars->nBTLimit/10) : p->pPars->nBTLimit;
+    int nConfEnd, nConfBeg, status, iVar0, iVar1, Lits[2];
+    int UnsatConflicts[3] = {0};
+    //printf( "%d ", nBTLimit );
+    if ( iObj1 <  iObj0 ) 
+         iObj1 ^= iObj0, iObj0 ^= iObj1, iObj1 ^= iObj0;
+    assert( iObj0 < iObj1 );    
+    *pfEasy = 0;
+    // check if SAT solver needs recycling
+    p->nCallsSince++; 
+    if ( p->nCallsSince > p->pPars->nCallsRecycle && 
+         Vec_IntSize(&p->pNew->vSuppVars) > p->pPars->nSatVarMax && p->pPars->nSatVarMax )
+        Cec5_ManSatSolverRecycle( p );
+    // add more logic to the solver
+    if ( !iObj0 && Cec5_ObjSatId(p->pNew, Gia_ManConst0(p->pNew)) == -1 )
+        Cec5_ObjSetSatId( p->pNew, Gia_ManConst0(p->pNew), sat_solver_addvar(p->pSat) );
+    clk = Abc_Clock();
+    Cec5_ManLoadInstance( p, iObj0, iObj1, &iVar0, &iVar1);
+    p->timeCnf += Abc_Clock() - clk;
+    // perform solving
+    Lits[0] = Abc_Var2Lit(iVar0, 1);
+    Lits[1] = Abc_Var2Lit(iVar1, fPhase);
+    sat_solver_set_conflict_budget( p->pSat, nBTLimit );
+    nConfBeg = sat_solver_conflictnum( p->pSat );
+    status = sat_solver_solve( p->pSat, Lits, 2 );
+    nConfEnd = sat_solver_conflictnum( p->pSat );
+    assert( nConfEnd >= nConfBeg );
+    p->nConflicts[2][2]  = Abc_MaxInt(p->nConflicts[2][2], nConfEnd - nConfBeg);
+    if ( fVerbose )
+    {
+        if ( status == GLUCOSE_SAT ) 
+        {
+            p->nConflicts[0][0] += nConfEnd == nConfBeg;
+            p->nConflicts[0][1] += nConfEnd -  nConfBeg;
+            p->nConflicts[0][2]  = Abc_MaxInt(p->nConflicts[0][2], nConfEnd - nConfBeg);
+            *pfEasy = nConfEnd == nConfBeg;
+        }
+        else if ( status == GLUCOSE_UNSAT ) 
+        {
+            if ( iObj0 > 0 )
+            {
+                UnsatConflicts[0] = nConfEnd == nConfBeg;
+                UnsatConflicts[1] = nConfEnd -  nConfBeg;
+                UnsatConflicts[2] = Abc_MaxInt(p->nConflicts[1][2], nConfEnd - nConfBeg);
+                p->nConflicts[1][2]  = Abc_MaxInt(p->nConflicts[1][2], UnsatConflicts[2]);
+            }
+            else
+            {
+                p->nConflicts[1][0] += nConfEnd == nConfBeg;
+                p->nConflicts[1][1] += nConfEnd -  nConfBeg;
+                p->nConflicts[1][2]  = Abc_MaxInt(p->nConflicts[1][2], nConfEnd - nConfBeg);
+                *pfEasy = nConfEnd == nConfBeg;
+            }
+        }
+    }
+    if ( status == GLUCOSE_UNSAT && iObj0 > 0 )
+    {
+        Lits[0] = Abc_Var2Lit(iVar0, 0);
+        Lits[1] = Abc_Var2Lit(iVar1, !fPhase);
+        sat_solver_set_conflict_budget( p->pSat, nBTLimit );
+        nConfBeg = sat_solver_conflictnum( p->pSat );
+        status = sat_solver_solve( p->pSat, Lits, 2 );
+        nConfEnd = sat_solver_conflictnum( p->pSat );
+        assert( nConfEnd >= nConfBeg );
+        p->nConflicts[2][2]  = Abc_MaxInt(p->nConflicts[2][2], nConfEnd - nConfBeg);
+        if ( fVerbose )
+        {
+            if ( status == GLUCOSE_SAT ) 
+            {
+                p->nConflicts[0][0] += nConfEnd == nConfBeg;
+                p->nConflicts[0][1] += nConfEnd -  nConfBeg;
+                p->nConflicts[0][2]  = Abc_MaxInt(p->nConflicts[0][2], nConfEnd - nConfBeg);
+                *pfEasy = nConfEnd == nConfBeg;
+            }
+            else if ( status == GLUCOSE_UNSAT ) 
+            {
+                UnsatConflicts[0]  &= nConfEnd == nConfBeg;
+                UnsatConflicts[1]  += nConfEnd -  nConfBeg;
+                UnsatConflicts[2]   = Abc_MaxInt(p->nConflicts[1][2], nConfEnd - nConfBeg);
+
+                p->nConflicts[1][0] += UnsatConflicts[0];
+                p->nConflicts[1][1] += UnsatConflicts[1];
+                p->nConflicts[1][2]  = Abc_MaxInt(p->nConflicts[1][2], UnsatConflicts[2]);
+                *pfEasy = UnsatConflicts[0];
+            }
+        }
+    }
+    //if ( status == GLUCOSE_UNDEC )
+    //    printf( "*  " );
+    return status;
+}
+void Cec5_FlushCache2Pattern( Cec5_Man_t * p ){
+    int j, iLit, nWrite = 0;
+    int iPatsOld = p->pAig->iPatsPi;
+    j = 0;
+    p->pAig->iPatsPi -- ;
+    while( j < p->vPiPatsCache->nSize ){
+        if( -1 < (iLit = p->vPiPatsCache->pArray[j++]) ){
+            Cec5_ObjSimSetInputBit( p->pAig, Abc_Lit2Var(iLit), Abc_LitIsCompl(iLit) );
+            continue;
+        }
+        p->pAig->iPatsPi -- ;
+        nWrite ++ ;
+    }
+    p->pAig->iPatsPi += nWrite+1;
+    assert( iPatsOld == p->pAig->iPatsPi );
+    p->vPiPatsCache->nSize = 0;
+}
+void Cec5_ClearCexMarks( Cec5_Man_t * p ){
+    Vec_IntFill( p->vCexStamps, Gia_ManObjNum(p->pAig), 0 );
+    Vec_BitFill( p->vCexSite  , Gia_ManObjNum(p->pAig), 0 );
+}
+void Cec5_ManCheckGlobalSim( Cec5_Man_t * p){
+    int iPatTop = p->pAig->iPatsPi;
+    if ( (iPatTop % (sizeof(word) * 8 * p->pAig->nSimWords / p->simBatchFactor)) == 0
+     || iPatTop == (int)sizeof(word) * 8 * p->pAig->nSimWords - 2 )
+    {
+        abctime clk2 = Abc_Clock();
+        Cec5_FlushCache2Pattern(p);
+        //p->simBound = iPatTop / (sizeof(word) * 8 * p->pAig->nSimWords / p->simBatchFactor)+2;//p->simTravId * p->LocalBatchSize / (sizeof(word) * 8<<3)+1;
+        p->simBound = iPatTop / (sizeof(word) * 8) + ((iPatTop % (sizeof(word) * 8)) ? 1: 0);
+        //if( iPatTop == sizeof(word) * 8 * p->pAig->nSimWords - 2 )
+        //    p->simBound += 1;
+        //printf("re-sim %5d %5d bound %5d\n", p->pAig->iPatsPi, p->simTravId, p->simBound );
+        Cec5_ManSimulate( p->pAig, p );
+        p->simBound = p->pPars->nWords;
+        //printf( "FasterSmall = %d.  FasterBig = %d.\n", p->nFaster[0], p->nFaster[1] );
+        p->nFaster[0] = p->nFaster[1] = 0;
+        //if ( p->nSatSat && p->nSatSat % 100 == 0 )
+            //Cec5_ManPrintStats( p->pAig, p->pPars, p, 0 );
+        Cec5_ClearCexMarks(p);
+        if( iPatTop == (int)sizeof(word) * 8 * p->pAig->nSimWords - 2 ){
+            Cec5_ManPrintStats( p->pAig, p->pPars, p, 0 );
+            p->pAig->iPatsPi = 0;
+            p->simTravId = 0;
+            p->simGlobalTop = 0;
+        } else {
+            //assert( 0 == iPatTop % (sizeof(word) * 8 * p->pAig->nSimWords) );
+            p->pAig->iPatsPi = iPatTop;
+            p->simGlobalTop = iPatTop / (sizeof(word) * 8 );
+        }
+        Vec_WrdFill( p->pAig->vSimsPi, Vec_WrdSize(p->pAig->vSimsPi), 0 );
+        p->timeResimGlo += Abc_Clock() - clk2;
+    }
+}
+int Cec5_ManSweepNode( Cec5_Man_t * p, int iObj, int iRepr )
+{
+    abctime clk = Abc_Clock();
+    int i, IdAig, IdSat, status, fEasy, RetValue = 1;
+    Gia_Obj_t * pObj = Gia_ManObj( p->pAig, iObj );
+    Gia_Obj_t * pRepr = Gia_ManObj( p->pAig, iRepr );
+    int fCompl = Abc_LitIsCompl(pObj->Value) ^ Abc_LitIsCompl(pRepr->Value) ^ pObj->fPhase ^ pRepr->fPhase;
+    int fEffort = p->vCoDrivers ? Vec_BitEntry(p->vCoDrivers, iObj) || Vec_BitEntry(p->vCoDrivers, iRepr) : 0;
+    status = Cec5_ManSolveTwo( p, Abc_Lit2Var(pRepr->Value), Abc_Lit2Var(pObj->Value), fCompl, &fEasy, p->pPars->fVerbose, fEffort );
+    if ( status == GLUCOSE_SAT )
+    {
+        int iLit;
+        Vec_BitWriteEntry( p->vCexSite, iObj, 1 );
+        //int iPatsOld = p->pAig->iPatsPi;
+        //printf( "Disproved: %d == %d.\n", Abc_Lit2Var(pRepr->Value), Abc_Lit2Var(pObj->Value) );
+        p->nSatSat++;
+        p->nPatterns++;
+        Vec_IntClear( p->vPat );
+        if ( p->pPars->jType == 0 )
+        {
+            Vec_IntForEachEntryDouble( &p->pNew->vCopiesTwo, IdAig, IdSat, i )
+                Vec_IntPush( p->vPat, Abc_Var2Lit(IdAig, sat_solver_read_cex_varvalue(p->pSat, IdSat)) );
+        }
+        else
+        {
+            int * pCex = sat_solver_read_cex( p->pSat );
+            int * pMap = Vec_IntArray(&p->pNew->vVarMap);
+            for ( i = 0; i < pCex[0]; )
+                Vec_IntPush( p->vPat, Abc_Lit2LitV(pMap, Abc_LitNot(pCex[++i])) );
+        }
+        assert( p->pAig->iPatsPi >= 0 && p->pAig->iPatsPi < 64 * p->pAig->nSimWords - 1 );
+        p->pAig->iPatsPi++;
+//        Vec_IntForEachEntry( p->vPat, iLit, i )
+//            Cec5_ObjSimSetInputBit( p->pAig, Abc_Lit2Var(iLit), Abc_LitIsCompl(iLit) );
+        Vec_IntForEachEntry( p->vPat, iLit, i )
+            Vec_IntPush( p->vPiPatsCache, iLit );
+        Vec_IntPush( p->vPiPatsCache, -1 );
+        if ( p->pAig->vPats )
+        {
+            Vec_IntPush( p->pAig->vPats, Vec_IntSize(p->vPat)+2 );
+            Vec_IntAppend( p->pAig->vPats, p->vPat );
+            Vec_IntPush( p->pAig->vPats, -1 );
+        }
+        //Cec5_ManPackAddPattern( p->pAig, p->vPat, 0 );
+        //assert( iPatsOld + 1 == p->pAig->iPatsPi );
+        if ( fEasy )
+            p->timeSatSat0 += Abc_Clock() - clk;
+        else
+            p->timeSatSat += Abc_Clock() - clk;
+        RetValue = 0;
+
+        p->simTravId = p->pAig->iPatsPi / p->LocalBatchSize;
+        if( (p->pAig->iPatsPi % p->LocalBatchSize) == 0 || 1 == p->LocalBatchSize )
+            Cec5_FlushCache2Pattern(p);
+
+        // this is not needed, but we keep it here anyway, because it takes very little time
+        //Cec5_ManVerify( p->pNew, Abc_Lit2Var(pRepr->Value), Abc_Lit2Var(pObj->Value), fCompl, p->pSat );
+        // resimulated once in a while
+        //if ( p->pAig->iPatsPi == 64 * p->pAig->nSimWords - 2 )
+        Cec5_ManCheckGlobalSim(p);
+    }
+    else if ( status == GLUCOSE_UNSAT )
+    {
+        //printf( "Proved: %d == %d.\n", Abc_Lit2Var(pRepr->Value), Abc_Lit2Var(pObj->Value) );
+        p->nSatUnsat++;
+        pObj->Value = Abc_LitNotCond( pRepr->Value, fCompl );
+        assert( !Gia_ObjProved( p->pAig, iObj ) );
+        Gia_ObjSetProved( p->pAig, iObj );
+        if ( iRepr == 0 )
+            p->iLastConst = iObj;
+        if ( fEasy )
+            p->timeSatUnsat0 += Abc_Clock() - clk;
+        else
+            p->timeSatUnsat += Abc_Clock() - clk;
+        RetValue = 1;
+    }
+    else 
+    {
+        p->nSatUndec++;
+        assert( status == GLUCOSE_UNDEC );
+        Gia_ObjSetFailed( p->pAig, iObj );
+        Vec_BitWriteEntry( p->vFails, iObj, 1 );
+        //if ( iRepr )
+        //Vec_BitWriteEntry( p->vFails, iRepr, 1 );
+        p->timeSatUndec += Abc_Clock() - clk;
+        RetValue = 2;
+    }
+    return RetValue;
+}
+Gia_Obj_t * Cec5_ManFindRepr( Gia_Man_t * p, Cec5_Man_t * pMan, int iObj )
+{
+    abctime clk = Abc_Clock();
+    Gia_Obj_t * pRepr = NULL;
+    int iMem, iRepr;
+    assert( Gia_ObjHasRepr(p, iObj) );
+    assert( !Gia_ObjProved(p, iObj) );
+    iRepr = Gia_ObjRepr(p, iObj);
+    assert( iRepr != iObj );
+    assert( !Gia_ObjProved(p, iRepr) );
+
+    pMan->simBound = pMan->simTravId * pMan->LocalBatchSize / (sizeof(word)<<3)+1;
+    assert( pMan->simBound <= pMan->pPars->nWords );
+
+    if( (Vec_BitEntry( pMan->vCexSite, iObj ) | Vec_BitEntry( pMan->vCexSite, iRepr ))
+        ||(Vec_IntEntry( pMan->vCexStamps, iObj ) != Vec_IntEntry( pMan->vCexStamps, iRepr )) ){
+        Cec5_ManSimulate_rec( p, pMan, iObj );
+        Cec5_ManSimulate_rec( p, pMan, iRepr );
+    }
+    if ( Cec5_ObjSimEqual(p, iObj, iRepr) )
+    {
+        pMan->timeResimLoc += Abc_Clock() - clk;
+        pRepr = Gia_ManObj(p, iRepr);
+        goto finalize;
+    }
+    Gia_ClassForEachObj1( p, iRepr, iMem )
+    {
+        if ( iObj == iMem )
+            break;
+        assert(iMem<iObj);
+        if ( Gia_ObjProved(p, iMem) || Gia_ObjFailed(p, iMem) )
+            continue;
+        if( Vec_IntEntry( pMan->vCexStamps, iObj ) != Vec_IntEntry( pMan->vCexStamps, iMem ) ){
+            Cec5_ManSimulate_rec( p, pMan, iMem );
+            Cec5_ManSimulate_rec( p, pMan, iObj );
+        }
+        if ( Cec5_ObjSimEqual(p, iObj, iMem) )
+        {
+            pMan->nFaster[0]++;
+            pMan->timeResimLoc += Abc_Clock() - clk;
+            pRepr = Gia_ManObj(p, iMem);
+            goto finalize;
+        }
+    }
+    pMan->nFaster[1]++;
+    pMan->timeResimLoc += Abc_Clock() - clk;
+finalize:
+    pMan->simBound = pMan->pPars->nWords;
+    return pRepr;
+}
+void Cec5_ManExtend( Cec5_Man_t * pMan, CbsP_Man_t * pCbs ){
+    while( pMan->pNew->vCopies2.nSize < Gia_ManObjNum(pMan->pNew) ){
+        Vec_IntPush( &pMan->pNew->vCopies2, -1 );
+        Vec_BitPush( pMan->vFails, 0 );
+        if( pCbs )
+            Vec_IntPush( pCbs->vValue, ~0 );
+    }
+}
+
+int Cec5_ManSweepNodeCbs( Cec5_Man_t * p, CbsP_Man_t * pCbs, int iObj, int iRepr, int fTagFail );
+int Cec5_ManPerformSweeping( Gia_Man_t * p, Cec_ParFra_t * pPars, Gia_Man_t ** ppNew, int fSimOnly, int fCbs, int approxLim, int subBatchSz, int adaRecycle )
+{
+    Gia_Obj_t * pObj, * pRepr; 
+    CbsP_Man_t * pCbs = NULL;
+    int i, fSimulate = 1;
+    int fPrep = 0;
+    int AccuSat = 0;
+    int * vMerged;
+    int go_back = -1;
+
+    Cec5_Man_t * pMan = Cec5_ManCreate( p, pPars ); 
+    pMan->approxLim = approxLim;
+    if( pMan->simBatchFactor != subBatchSz ){
+        printf("overwrite default batch size: from %3d to %3d\n", pMan->simBatchFactor, subBatchSz);
+        pMan->simBatchFactor = subBatchSz;
+    }
+    if( pMan->adaRecycle != adaRecycle ){
+        printf("overwrite default adaptive recycle: from %3d to %3d\n", pMan->adaRecycle, adaRecycle);
+        pMan->adaRecycle = adaRecycle;
+    }
+    if ( pPars->fVerbose )
+        printf( "Solver type = %d. Simulate %d words in %d rounds. SAT with %d confs. Recycle after %d SAT calls.\n", 
+            pPars->jType, pPars->nWords, pPars->nRounds, pPars->nBTLimit, pPars->nCallsRecycle );
+
+    if( fPrep )
+        pMan->fEec = 1;
+
+
+    // this is currently needed to have a correct mapping
+    Gia_ManForEachCi( p, pObj, i )
+        assert( Gia_ObjId(p, pObj) == i+1 );
+
+    // check if any output trivially fails under all-0 pattern
+    Gia_ManRandom( 1 );
+    Gia_ManSetPhase( p );
+    if ( pPars->nLevelMax )
+        Gia_ManLevelNum(p);
+    //Gia_ManStaticFanoutStart( p );
+    if ( pPars->fCheckMiter ) 
+    {
+        Gia_ManForEachCo( p, pObj, i )
+            if ( pObj->fPhase )
+            {
+                p->pCexSeq = Cec5_ManDeriveCex( p, i, -1 );
+                goto finalize;
+            }
+    }
+
+    // simulate one round and create classes
+    Cec5_ManSimAlloc( p, pPars->nWords, 0 );
+    Cec5_ManSimulateCis( p );
+    Cec5_ManSimulate( p, pMan );
+    if ( pPars->fCheckMiter && !Cec5_ManSimulateCos(p) ) // cex detected
+        goto finalize;
+    if ( pPars->fVerbose )
+        Cec5_ManPrintStats( p, pPars, pMan, 1 );
+
+    // perform simulation
+    for ( i = 0; i < pPars->nRounds; i++ )
+    {
+        Cec5_ManSimulateCis( p );
+        Cec5_ManSimulate( p, pMan );
+        if ( pPars->fCheckMiter && !Cec5_ManSimulateCos(p) ) // cex detected
+            goto finalize;
+        if ( i && i % (pPars->nRounds / 5) == 0 && pPars->fVerbose )
+            Cec5_ManPrintStats( p, pPars, pMan, 1 );
+    }
+    if ( fSimOnly )
+        goto finalize;
+    
+
+    // perform additional simulation
+    Cec5_ManCandIterStart( pMan );
+    for ( i = 0; fSimulate && i < pPars->nGenIters; i++ )
+    {
+        Cec5_ManSimulateCis( p );
+        fSimulate = Cec5_ManGeneratePatterns( pMan );
+        Cec5_ManSimulate( p, pMan );
+        if ( pPars->fCheckMiter && !Cec5_ManSimulateCos(p) ) // cex detected
+            goto finalize;
+        if ( i && i % 5 == 0 && pPars->fVerbose )
+            Cec5_ManPrintStats( p, pPars, pMan, 1 );
+        if( pMan->nSatSat - AccuSat < p->nSimWords * (int)sizeof(word) * 8 )
+            break;
+
+        AccuSat = pMan->nSatSat;
+    }
+    if ( i && i % 5 && pPars->fVerbose )
+        Cec5_ManPrintStats( p, pPars, pMan, 1 );
+
+    vMerged = ABC_FALLOC(int, Gia_ManObjNum(p)); // refinement may move non-repr merge around . record the true merged performed
+
+    p->iPatsPi = 0;
+    Vec_WrdFill( p->vSimsPi, Vec_WrdSize(p->vSimsPi), 0 );
+    pMan->nSatSat = 0;
+    pMan->pNew = Cec5_ManStartNew( p );
+
+    if( fCbs ){
+        //Gia_ManCreateRefs( pMan->pNew );
+        pMan->pNew->pRefs = ABC_CALLOC( int, Gia_ManObjNum(p) );
+        Gia_ManCleanMark0( pMan->pNew );
+        Gia_ManCleanMark1( pMan->pNew );
+        Gia_ManFillValue ( pMan->pNew );
+        pCbs = CbsP_ManAlloc( p );
+        pCbs->pAig = pMan->pNew;
+        pCbs->Pars.nBTLimit    = 100;//pPars->nBTLimit;
+        pCbs->Pars.nJustLimit  = 100;
+        pCbs->Pars.nJscanLimit = 100;
+        pCbs->Pars.nRscanLimit = 100;
+        pCbs->Pars.nPropLimit  = 100;
+
+        if( pPars->fVerbose ){
+            printf("cbs: clim = %4d jlim = %4d\n"
+                , pCbs->Pars.nBTLimit
+                , pCbs->Pars.nJustLimit );
+        }
+    }
+    
+    //Gia_ManForEachAnd( p, pObj, i )
+    i = 0;
+resume:
+    for( ; i < Gia_ManObjNum(p) && (pObj = Gia_ManObj(p,i)); i ++ )
+    {
+        int status = 2;
+        Gia_Obj_t * pObjNew; 
+        if ( !Gia_ObjIsAnd(pObj) )
+            continue;
+        
+        Vec_BitWriteEntry( pMan->vCexSite, i
+            , Vec_BitEntry( pMan->vCexSite, Gia_ObjFaninId0(pObj,i) ) 
+            | Vec_BitEntry( pMan->vCexSite, Gia_ObjFaninId1(pObj,i) ) );
+
+        if ( Gia_ObjFailed(p,i) )
+            continue;
+        pMan->nAndNodes++;
+        if ( Gia_ObjProved(p, i) ){
+            pRepr = Gia_ManObj( p, vMerged[i] );
+            pObj->Value = Abc_LitNotCond( pRepr->Value, pObj->fPhase ^ pRepr->fPhase ); // upate in case repr rehashed due to fanin its backtrace
+            continue;
+        }
+
+        if ( Gia_ObjIsXor(pObj) )
+            pObj->Value = Gia_ManHashXorReal( pMan->pNew, Gia_ObjFanin0Copy(pObj), Gia_ObjFanin1Copy(pObj) );
+        else
+            pObj->Value = Gia_ManHashAnd( pMan->pNew, Gia_ObjFanin0Copy(pObj), Gia_ObjFanin1Copy(pObj) );
+
+        Cec5_ManExtend( pMan, pCbs );
+
+        if ( pPars->nLevelMax && Gia_ObjLevel(p, pObj) > pPars->nLevelMax )
+            continue;
+
+        pObjNew = Gia_ManObj( pMan->pNew, Abc_Lit2Var(pObj->Value) );
+        if ( Gia_ObjIsAnd(pObjNew) )
+        if ( Vec_BitEntry(pMan->vFails, Gia_ObjFaninId0(pObjNew, Abc_Lit2Var(pObj->Value))) || 
+             Vec_BitEntry(pMan->vFails, Gia_ObjFaninId1(pObjNew, Abc_Lit2Var(pObj->Value))) )
+            Vec_BitWriteEntry( pMan->vFails, Abc_Lit2Var(pObjNew->Value), 1 );
+        //if ( Gia_ObjIsAnd(pObjNew) )
+        //    Gia_ObjSetAndLevel( pMan->pNew, pObjNew );
+        // select representative based on candidate equivalence classes
+        pRepr = Gia_ObjReprObj( p, i );
+
+        if ( pRepr == NULL )
+            continue;
+        
+        if ( 1 ) // select representative based on recent counter-examples
+        {
+            pRepr = Cec5_ManFindRepr( p, pMan, i );
+            if ( pRepr == NULL )
+                continue;
+        }
+        if ( Abc_Lit2Var(pObj->Value) == Abc_Lit2Var(pRepr->Value) )
+        {
+            assert( (pObj->Value ^ pRepr->Value) == (pObj->fPhase ^ pRepr->fPhase) );
+            vMerged[i] = Gia_ObjId(p, pRepr);
+            Gia_ObjSetProved( p, i );
+            if ( Gia_ObjId(p, pRepr) == 0 )
+                pMan->iLastConst = i;
+
+            continue;
+        }
+
+        if ( fCbs && (status = Cec5_ManSweepNodeCbs(pMan, pCbs, i, Gia_ObjId(p, pRepr), 0)) && Gia_ObjProved(p, i) ){
+            vMerged[i] = Gia_ObjId(p, pRepr);
+            pObj->Value = Abc_LitNotCond( pRepr->Value, pObj->fPhase ^ pRepr->fPhase );
+        }
+
+        if ( 2 == status && (status = Cec5_ManSweepNode(pMan, i, Gia_ObjId(p, pRepr))) && Gia_ObjProved(p, i) ){
+            vMerged[i] = Gia_ObjId(p, pRepr);
+            pObj->Value = Abc_LitNotCond( pRepr->Value, pObj->fPhase ^ pRepr->fPhase );
+        }
+
+        if( 0 == status && -1 == go_back )
+            go_back = i;
+
+        if( 0 == pMan->nPatterns || 0!=status || pMan->nPatterns % (64 * p->nSimWords-2) )
+            continue;
+
+        if( -1 < go_back ){
+            //printf("go back to %6d from %6d\n", go_back, i );
+            pMan->nAndNodes -= i-go_back;
+            i = go_back-1, go_back = -1;
+        }
+    }
+    if ( p->iPatsPi > 0 )
+    {
+        abctime clk2 = Abc_Clock();
+        Cec5_FlushCache2Pattern(pMan);
+        Cec5_ManSimulate( p, pMan );
+        p->iPatsPi = 0;
+        pMan->simTravId = 0;
+        pMan->simGlobalTop = 0;
+        Cec5_ClearCexMarks(pMan);
+        pMan->timeResimGlo += Abc_Clock() - clk2;
+        if( -1 < go_back ){
+            i = go_back - 1;
+            go_back = -1;
+            goto resume;
+        }
+    }
+
+    ABC_FREE(vMerged);
+
+    if ( pPars->fVerbose )
+        Cec5_ManPrintStats( p, pPars, pMan, 0 );
+    if ( ppNew )
+    {
+        Gia_ManForEachCo( p, pObj, i )
+            pObj->Value = Gia_ManAppendCo( pMan->pNew, Gia_ObjFanin0Copy(pObj) );
+        *ppNew = Gia_ManCleanup( pMan->pNew );
+    }
+
+    if( fCbs ){
+        if ( pPars->fVerbose ){
+            CbsP_ManSatPrintStats( pCbs );
+            CbsP_PrintRecord(&pCbs->Pars);
+        }
+    }
+finalize:
+    if ( pPars->fVerbose )
+        printf( "SAT calls = %d:  P = %d (0=%d a=%.2f m=%d)  D = %d (0=%d a=%.2f m=%d)  F = %d   Sim = %d  Recyc = %d  Xor = %.2f %%\n", 
+            pMan->nSatUnsat + pMan->nSatSat + pMan->nSatUndec, 
+            pMan->nSatUnsat, pMan->nConflicts[1][0], (float)pMan->nConflicts[1][1]/Abc_MaxInt(1, pMan->nSatUnsat-pMan->nConflicts[1][0]), pMan->nConflicts[1][2],
+            pMan->nSatSat,   pMan->nConflicts[0][0], (float)pMan->nConflicts[0][1]/Abc_MaxInt(1, pMan->nSatSat  -pMan->nConflicts[0][0]), pMan->nConflicts[0][2],  
+            pMan->nSatUndec,  
+            pMan->nSimulates, pMan->nRecycles, 100.0*pMan->nGates[1]/Abc_MaxInt(1, pMan->nGates[0]+pMan->nGates[1]) );
+    Cec5_ManDestroy( pMan );
+    if( pCbs )
+        CbsP_ManStop(pCbs);
+    //Gia_ManStaticFanoutStop( p );
+    //Gia_ManEquivPrintClasses( p, 1, 0 );
+    return p->pCexSeq ? 0 : 1;
+}
+Gia_Man_t * Cec5_ManSimulateTest( Gia_Man_t * p, Cec_ParFra_t * pPars, int fCbs, int approxLim, int subBatchSz, int adaRecycle )
+{
+    Gia_Man_t * pNew = NULL;
+    Cec5_ManPerformSweeping( p, pPars, &pNew, 0, fCbs, approxLim, subBatchSz, adaRecycle );
+    return pNew;
+}
+
+
+
+int Cec5_ManSolveTwoCbs( Cec5_Man_t * p, CbsP_Man_t * pCbs, int iObj0, int iObj1, int fPhase, int * pfEasy, int fVerbose, int fEffort )
+{
+//    abctime clk;
+//    int nBTLimit = fEffort ? p->pPars->nBTLimitPo : (Vec_BitEntry(p->vFails, iObj0) || Vec_BitEntry(p->vFails, iObj1)) ? Abc_MaxInt(1, p->pPars->nBTLimit/10) : p->pPars->nBTLimit;
+    Gia_Obj_t * pRepr, * pObj;
+    int nConfEnd, nConfBeg, status;//, iVar0, iVar1, Lits[2];
+    int UnsatConflicts[3] = {0};
+    //printf( "%d ", nBTLimit );
+    if ( iObj1 <  iObj0 ) 
+         iObj1 ^= iObj0, iObj0 ^= iObj1, iObj1 ^= iObj0;
+    assert( iObj0 < iObj1 );
+    pRepr = Gia_ManObj( p->pNew, iObj0 );
+    pObj  = Gia_ManObj( p->pNew, iObj1 );
+    *pfEasy = 0;
+    // check if SAT solver needs recycling
+    p->nCallsSince++; 
+//    if ( p->nCallsSince > p->pPars->nCallsRecycle && 
+//         Vec_IntSize(&p->pNew->vSuppVars) > p->pPars->nSatVarMax && p->pPars->nSatVarMax )
+//        Cec5_ManSatSolverRecycle( p );
+//    // add more logic to the solver
+//    if ( !iObj0 && Cec5_ObjSatId(p->pNew, Gia_ManConst0(p->pNew)) == -1 )
+//        Cec5_ObjSetSatId( p->pNew, Gia_ManConst0(p->pNew), sat_solver_addvar(p->pSat) );
+//    clk = Abc_Clock();
+//    iVar0 = Cec5_ObjGetCnfVar( p, iObj0 );
+//    iVar1 = Cec5_ObjGetCnfVar( p, iObj1 );
+//    if( p->pPars->jType > 0 )
+//    {
+//        sat_solver_start_new_round( p->pSat );
+//        sat_solver_mark_cone( p->pSat, Cec5_ObjSatId(p->pNew, Gia_ManObj(p->pNew, iObj0)) );
+//        sat_solver_mark_cone( p->pSat, Cec5_ObjSatId(p->pNew, Gia_ManObj(p->pNew, iObj1)) );
+//    }
+//    p->timeCnf += Abc_Clock() - clk;
+    // perform solving
+//    Lits[0] = Abc_Var2Lit(iVar0, 1);
+//    Lits[1] = Abc_Var2Lit(iVar1, fPhase);
+//    sat_solver_set_conflict_budget( p->pSat, nBTLimit );
+//    nConfBeg = sat_solver_conflictnum( p->pSat );
+//    status = sat_solver_solve( p->pSat, Lits, 2 );
+//    nConfEnd = sat_solver_conflictnum( p->pSat );
+    nConfBeg = 0;
+    if( !Gia_ObjIsConst0(pRepr) )
+        status = CbsP_ManSolve2(pCbs,Gia_Not(pObj),Gia_NotCond(pRepr, fPhase));
+    else
+        status = CbsP_ManSolve2(pCbs,Gia_NotCond(pObj,fPhase),NULL);
+    nConfEnd = pCbs->Pars.nBTThis;
+    assert( nConfEnd >= nConfBeg );
+    if ( fVerbose )
+    {
+        if ( status == CBS_SAT ) 
+        {
+            p->nConflicts[0][0] += nConfEnd == nConfBeg;
+            p->nConflicts[0][1] += nConfEnd -  nConfBeg;
+            p->nConflicts[0][2]  = Abc_MaxInt(p->nConflicts[0][2], nConfEnd - nConfBeg);
+            *pfEasy = nConfEnd == nConfBeg;
+        }
+        else if ( status == CBS_UNSAT ) 
+        {
+            if ( iObj0 > 0 )
+            {
+                UnsatConflicts[0] = nConfEnd == nConfBeg;
+                UnsatConflicts[1] = nConfEnd -  nConfBeg;
+                UnsatConflicts[2] = Abc_MaxInt(p->nConflicts[1][2], nConfEnd - nConfBeg);
+            }
+            else
+            {
+                p->nConflicts[1][0] += nConfEnd == nConfBeg;
+                p->nConflicts[1][1] += nConfEnd -  nConfBeg;
+                p->nConflicts[1][2]  = Abc_MaxInt(p->nConflicts[1][2], nConfEnd - nConfBeg);
+                *pfEasy = nConfEnd == nConfBeg;
+            }
+        }
+    }
+    if ( status == CBS_UNSAT && iObj0 > 0 )
+    {
+        //Lits[0] = Abc_Var2Lit(iVar0, 0);
+        //Lits[1] = Abc_Var2Lit(iVar1, !fPhase);
+        //sat_solver_set_conflict_budget( p->pSat, nBTLimit );
+        //nConfBeg = sat_solver_conflictnum( p->pSat );
+        //status = sat_solver_solve( p->pSat, Lits, 2 );
+        //nConfEnd = sat_solver_conflictnum( p->pSat );
+        nConfBeg = 0;
+        status = CbsP_ManSolve2(pCbs,pObj,Gia_NotCond(pRepr,!fPhase));
+        nConfEnd = pCbs->Pars.nBTThis;
+        assert( nConfEnd >= nConfBeg );
+        if ( fVerbose )
+        {
+            if ( status == CBS_SAT ) 
+            {
+                p->nConflicts[0][0] += nConfEnd == nConfBeg;
+                p->nConflicts[0][1] += nConfEnd -  nConfBeg;
+                p->nConflicts[0][2]  = Abc_MaxInt(p->nConflicts[0][2], nConfEnd - nConfBeg);
+                *pfEasy = nConfEnd == nConfBeg;
+            }
+            else if ( status == CBS_UNSAT ) 
+            {
+                UnsatConflicts[0]  &= nConfEnd == nConfBeg;
+                UnsatConflicts[1]  += nConfEnd -  nConfBeg;
+                UnsatConflicts[2]   = Abc_MaxInt(p->nConflicts[1][2], nConfEnd - nConfBeg);
+
+                p->nConflicts[1][0] += UnsatConflicts[0];
+                p->nConflicts[1][1] += UnsatConflicts[1];
+                p->nConflicts[1][2]  = Abc_MaxInt(p->nConflicts[1][2], UnsatConflicts[2]);
+                *pfEasy = UnsatConflicts[0];
+            }
+        }
+    }
+    //if ( status == GLUCOSE_UNDEC )
+    //    printf( "*  " );
+    return status;
+}
+
+
+int Cec5_ManSweepNodeCbs( Cec5_Man_t * p, CbsP_Man_t * pCbs, int iObj, int iRepr, int fTagFail )
+{
+    extern int CbsP_ManSolve2( CbsP_Man_t * p, Gia_Obj_t * pObj, Gia_Obj_t * pObj2 );
+    abctime clk = Abc_Clock();
+    int i, status, fEasy, RetValue = 1;
+    Gia_Obj_t * pObj = Gia_ManObj( p->pAig, iObj );
+    Gia_Obj_t * pRepr = Gia_ManObj( p->pAig, iRepr );
+    int fCompl = Abc_LitIsCompl(pObj->Value) ^ Abc_LitIsCompl(pRepr->Value) ^ pObj->fPhase ^ pRepr->fPhase;
+    //int fCompl = pObj->fPhase ^ pRepr->fPhase;
+    int fEffort = p->vCoDrivers ? Vec_BitEntry(p->vCoDrivers, iObj) || Vec_BitEntry(p->vCoDrivers, iRepr) : 0;
+    //status = Cec5_ManSolveTwo( p, Abc_Lit2Var(pRepr->Value), Abc_Lit2Var(pObj->Value), fCompl, &fEasy, p->pPars->fVerbose, fEffort );
+
+    status = Cec5_ManSolveTwoCbs( p, pCbs, Abc_Lit2Var(pRepr->Value), Abc_Lit2Var(pObj->Value), fCompl, &fEasy, p->pPars->fVerbose, fEffort );
+    //status = CbsP_ManSolve2(pCbs,pObj,pRepr);
+    if ( status == CBS_SAT )
+    {
+        int iLit;
+        Vec_BitWriteEntry( p->vCexSite, iObj, 1 );
+//        int iPatsOld = p->pAig->iPatsPi;
+//        //printf( "Disproved: %d == %d.\n", Abc_Lit2Var(pRepr->Value), Abc_Lit2Var(pObj->Value) );
+        p->nSatSat++;
+        p->nPatterns++;
+        Vec_IntClear( p->vPat );
+        Vec_IntForEachEntry( pCbs->vModel, iLit, i )
+            Vec_IntPush( p->vPat, Abc_LitNot(iLit) );
+        assert( p->pAig->iPatsPi >= 0 && p->pAig->iPatsPi < 64 * p->pAig->nSimWords - 1 );
+        p->pAig->iPatsPi++;
+        Vec_IntForEachEntry( p->vPat, iLit, i )
+            Vec_IntPush( p->vPiPatsCache, iLit );
+        Vec_IntPush( p->vPiPatsCache, -1 );
+
+        if ( fEasy )
+            p->timeSatSat0 += Abc_Clock() - clk;
+        else
+            p->timeSatSat += Abc_Clock() - clk;
+        RetValue = 0;
+
+        p->simTravId = p->pAig->iPatsPi / p->LocalBatchSize;
+        if( (p->pAig->iPatsPi % p->LocalBatchSize) == 0 || 1 == p->LocalBatchSize )
+            Cec5_FlushCache2Pattern(p);
+
+//        // this is not needed, but we keep it here anyway, because it takes very little time
+//        //Cec5_ManVerify( p->pNew, Abc_Lit2Var(pRepr->Value), Abc_Lit2Var(pObj->Value), fCompl, p->pSat );
+//        // resimulated once in a while
+        Cec5_ManCheckGlobalSim(p);
+    }
+    else if ( status == CBS_UNSAT )
+    {
+        //printf( "Proved: %d == %d.\n", Abc_Lit2Var(pRepr->Value), Abc_Lit2Var(pObj->Value) );
+        p->nSatUnsat++;
+        pObj->Value = Abc_LitNotCond( pRepr->Value, fCompl );
+        assert( !Gia_ObjProved( p->pAig, iObj ) );
+        Gia_ObjSetProved( p->pAig, iObj );
+        if ( iRepr == 0 )
+            p->iLastConst = iObj;
+        if ( fEasy )
+            p->timeSatUnsat0 += Abc_Clock() - clk;
+        else
+            p->timeSatUnsat += Abc_Clock() - clk;
+        RetValue = 1;
+    }
+    else 
+    {
+        if( fTagFail ){
+            p->nSatUndec++;
+            assert( status == CBS_UNDEC );
+            Gia_ObjSetFailed( p->pAig, iObj );
+            Gia_ObjSetFailed( p->pAig, iRepr );
+            Vec_BitWriteEntry( p->vFails, iObj, 1 );
+            p->timeSatUndec += Abc_Clock() - clk;
+        }
+        //if ( iRepr )
+        //Vec_BitWriteEntry( p->vFails, iRepr, 1 );
+        RetValue = 2;
+    }
+    return RetValue;
+}
+
+////////////////////////////////////////////////////////////////////////
+///                       END OF FILE                                ///
+////////////////////////////////////////////////////////////////////////
+
+
+ABC_NAMESPACE_IMPL_END
+
diff --git a/src/proof/cec/module.make b/src/proof/cec/module.make
index 23595f23..ed3dac11 100644
--- a/src/proof/cec/module.make
+++ b/src/proof/cec/module.make
@@ -9,6 +9,7 @@ SRC +=    src/proof/cec/cecCec.c \
     src/proof/cec/cecSat.c \
     src/proof/cec/cecSatG.c \
     src/proof/cec/cecSatG2.c \
+    src/proof/cec/cecSatG3.c \
     src/proof/cec/cecSeq.c \
     src/proof/cec/cecSim.c \
     src/proof/cec/cecSolve.c \
diff --git a/src/sat/glucose2/AbcGlucose2.cpp b/src/sat/glucose2/AbcGlucose2.cpp
index 9a8b97eb..c1d77587 100644
--- a/src/sat/glucose2/AbcGlucose2.cpp
+++ b/src/sat/glucose2/AbcGlucose2.cpp
@@ -1536,6 +1536,12 @@ int Glucose2_SolveAig(Gia_Man_t * p, Glucose2_Pars * pPars)
     return (ret == l_True ? 10 : ret == l_False ? 20 : 0);
 }
 
+extern "C" {
+    void glucose2_markapprox( void * pSat, int v0, int v1, int nlim ){
+        ((Gluco2::Solver*) pSat)->markApprox(v0, v1, nlim);
+    }
+};
+
 ////////////////////////////////////////////////////////////////////////
 ///                       END OF FILE                                ///
 ////////////////////////////////////////////////////////////////////////
diff --git a/src/sat/glucose2/CGlucoseCore.h b/src/sat/glucose2/CGlucoseCore.h
index c0f96fc4..22de92d2 100644
--- a/src/sat/glucose2/CGlucoseCore.h
+++ b/src/sat/glucose2/CGlucoseCore.h
@@ -613,6 +613,85 @@ inline void Solver::prelocate( int base_var_num ){
 	polarity   .prelocate( base_var_num );
 }
 
+
+inline void Solver::markTill( Var v, int nlim ){
+	if( var2TravId[v] == travId )
+		return;
+
+	vMarked.push(v);
+	
+	if( vMarked.size() >= nlim )
+		return;
+	if( var2TravId[v] == travId-1 || !isTwoFanin(v) )
+		goto finalize;
+
+	markTill( getFaninVar0(v), nlim );
+	markTill( getFaninVar1(v), nlim );
+finalize:
+	var2TravId[v] = travId;
+}
+
+inline void Solver::markApprox( Var v0, Var v1, int nlim ){
+    int i;
+	if( travId <= 1 || nSkipMark>=4 || 0 == nlim )
+		goto finalize;
+
+	vMarked.shrink_( vMarked.size() );
+	travId ++ ; // travId = t+1
+	assert(travId>1);
+
+	markTill(v0, nlim);
+	if( vMarked.size() >= nlim )
+		goto finalize;
+
+	markTill(v1, nlim);
+	if( vMarked.size() >= nlim )
+		goto finalize;
+
+	travId -- ; // travId = t
+	for(i = 0; i < vMarked.size(); i ++){
+		var2TravId  [ vMarked[i] ]      = travId;   // set new nodes to time t 
+		var2NodeData[ vMarked[i] ].sort = 0;
+	}
+	nSkipMark ++ ;
+	return;
+finalize:
+
+	travId ++ ;
+	nSkipMark = 0;
+	markCone(v0);
+	markCone(v1);
+}
+
+inline void Solver::loadJust_rec( Var v ){
+	//assert( value(v) != l_Undef );
+	if( var2TravId[v] == travId || value(v) == l_Undef )
+		return;
+	assert( var2TravId[v] == travId-1 );
+	var2TravId[v] = travId;
+	vMarked.push(v);
+
+	if( !isTwoFanin(v) ){
+		JustModel.push( mkLit( v, value(v) == l_False ) );
+		return;
+	}
+	loadJust_rec( getFaninVar0(v) );
+	loadJust_rec( getFaninVar1(v) );
+}
+inline void Solver::loadJust(){
+    int i;
+	travId ++ ;
+	JustModel.shrink_(JustModel.size());
+	vMarked.shrink_(vMarked.size());
+	JustModel.push(toLit(0));
+	for(i = 0; i < assumptions.size(); i ++)
+		loadJust_rec( var(assumptions[i]) );
+	JustModel[0] = toLit( JustModel.size()-1 );
+	travId -- ;
+	for(i = 0; i < vMarked.size(); i ++)
+		var2TravId[ vMarked[i] ] = travId;
+}
+
 };
 
 ABC_NAMESPACE_IMPL_END
diff --git a/src/sat/glucose2/Glucose2.cpp b/src/sat/glucose2/Glucose2.cpp
index 4b4c28e7..d345cd0a 100644
--- a/src/sat/glucose2/Glucose2.cpp
+++ b/src/sat/glucose2/Glucose2.cpp
@@ -186,6 +186,7 @@ Solver::Solver() :
   itpc = ca.alloc(tmp);
   ca[itpc].shrink( ca[itpc].size() );
 
+  nSkipMark = 0;
   #endif
 }
 
@@ -1452,15 +1453,20 @@ printf("c ==================================[ Search Statistics (every %6d confl
     if (status == l_True){
 
         if( justUsage() ){
-            JustModel.shrink_(JustModel.size());
-            assert(jheap.empty());
-            //JustModel.growTo(nVars());
-            int i = 0, j = 0;
-            JustModel.push(toLit(0));
-            for (; i < trail.size(); i++) 
-                if( isRoundWatch(var(trail[i])) && !isTwoFanin(var(trail[i])) )
-                    JustModel.push(trail[i]), j++;
-            JustModel[0] = toLit(j);
+            if( nSkipMark ){
+                loadJust();
+            } else {
+                JustModel.shrink_(JustModel.size());
+                assert(jheap.empty());
+                //JustModel.growTo(nVars());
+                int i = 0, j = 0;
+                JustModel.push(toLit(0));
+                for (; i < trail.size(); i++) 
+                    if( isRoundWatch(var(trail[i])) && !isTwoFanin(var(trail[i])) )
+                        JustModel.push(trail[i]), j++;
+                JustModel[0] = toLit(j);
+            }
+            
         } else {
             // Extend & copy model:
             model.shrink_(model.size());
@@ -1743,6 +1749,9 @@ void Solver::reset()
         itpc = ca.alloc(tmp);
         ca[itpc].shrink( ca[itpc].size() );
     }
+
+    vMarked.shrink_( vMarked.size() );
+    nSkipMark = 0;
     #endif
 }
 
diff --git a/src/sat/glucose2/Solver.h b/src/sat/glucose2/Solver.h
index b1d38d79..004fdc95 100644
--- a/src/sat/glucose2/Solver.h
+++ b/src/sat/glucose2/Solver.h
@@ -453,7 +453,15 @@ protected:
     Heap2<JustOrderLt2, JustKey> jheap;
     vec<int> jlevel;
     vec<int> jnext;
+
+    int nSkipMark;
+    void loadJust_rec( Var v );
+    void loadJust();
+    vec<Var> vMarked;
 public:
+    void markTill( Var v0, int nlim );
+    void markApprox( Var v0, Var v1, int nlim );
+
     void prelocate( int var_num );
     void setVarFaninLits( Var v, Lit lit1, Lit lit2 );
     void setVarFaninLits( int v, int lit1, int lit2 ){ setVarFaninLits( Var(v), toLit(lit1), toLit(lit2) ); }