giaCSat2.c

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#include "gia.h"
 
ABC_NAMESPACE_IMPL_START
 
 
//#define gia_assert(exp)     ((void)0)
//#define gia_assert(exp)     (assert(exp))

 
typedef struct Cbs2_Par_t_ Cbs2_Par_t;
struct Cbs2_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
    int           fUseFanout;   // use node with the largest fanin fanout
    // other
    int           fVerbose;
};
 
typedef struct Cbs2_Que_t_ Cbs2_Que_t;
struct Cbs2_Que_t_
{
    int           iHead;        // beginning of the queue
    int           iTail;        // end of the queue
    int           nSize;        // allocated size
    int *         pData;        // nodes stored in the queue
};
 
typedef struct Cbs2_Man_t_ Cbs2_Man_t;
struct Cbs2_Man_t_
{
    Cbs2_Par_t    Pars;         // parameters
    Gia_Man_t *   pAig;         // AIG manager
    Cbs2_Que_t    pProp;        // propagation queue
    Cbs2_Que_t    pJust;        // justification queue
    Cbs2_Que_t    pClauses;     // clause queue
    Vec_Int_t *   vModel;       // satisfying assignment
    Vec_Int_t *   vTemp;        // temporary storage
    // internal data
    Vec_Str_t     vAssign;
    Vec_Str_t     vMark;
    Vec_Int_t     vLevReason;
    Vec_Int_t     vWatches;
    Vec_Int_t     vWatchUpds;
    Vec_Int_t     vFanoutN;
    Vec_Int_t     vFanout0;
    Vec_Int_t     vActivity;
    Vec_Int_t     vActStore;
    Vec_Int_t     vJStore;
    // 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       timeJFront;
    abctime       timeSatUnsat; // unsat
    abctime       timeSatSat;   // sat
    abctime       timeSatUndec; // undecided
    abctime       timeTotal;    // total runtime
    // other statistics
    int           nPropCalls[3];
    int           nFails[2];
    int           nClauseConf;
};
 
static inline int   Cbs2_VarUnused( Cbs2_Man_t * p, int iVar )                     { return Vec_IntEntry(&p->vLevReason, 3*iVar) == -1; }
static inline void  Cbs2_VarSetUnused( Cbs2_Man_t * p, int iVar )                  { Vec_IntWriteEntry(&p->vLevReason, 3*iVar, -1);     } 
 
/*
static inline int   Cbs2_VarMark0( Cbs2_Man_t * p, int iVar )                      { return Vec_StrEntry(&p->vAssign, iVar);            }
static inline void  Cbs2_VarSetMark0( Cbs2_Man_t * p, int iVar, int Value )        { Vec_StrWriteEntry(&p->vAssign, iVar, (char)Value); } 
 
static inline int   Cbs2_VarMark1( Cbs2_Man_t * p, int iVar )                      { return Vec_StrEntry(&p->vValue, iVar);             }
static inline void  Cbs2_VarSetMark1( Cbs2_Man_t * p, int iVar, int Value )        { Vec_StrWriteEntry(&p->vValue, iVar, (char)Value);  } 
 
static inline int   Cbs2_VarIsAssigned( Cbs2_Man_t * p, int iVar )                 { return Cbs2_VarMark0(p, iVar);                                                                  }
static inline void  Cbs2_VarAssign( Cbs2_Man_t * p, int iVar )                     { assert(!Cbs2_VarIsAssigned(p, iVar)); Cbs2_VarSetMark0(p, iVar, 1);                             }
static inline void  Cbs2_VarUnassign( Cbs2_Man_t * p, int iVar )                   { assert( Cbs2_VarIsAssigned(p, iVar)); Cbs2_VarSetMark0(p, iVar, 0); Cbs2_VarSetUnused(p, iVar); }
static inline int   Cbs2_VarValue( Cbs2_Man_t * p, int iVar )                      { assert( Cbs2_VarIsAssigned(p, iVar)); return Cbs2_VarMark1(p, iVar);                            }
static inline void  Cbs2_VarSetValue( Cbs2_Man_t * p, int iVar, int v )            { assert( Cbs2_VarIsAssigned(p, iVar)); Cbs2_VarSetMark1(p, iVar, v);                             }
 
static inline int   Cbs2_VarIsJust( Cbs2_Man_t * p, Gia_Obj_t * pVar, int iVar )      { return Gia_ObjIsAnd(pVar) && !Cbs2_VarIsAssigned(p, Gia_ObjFaninId0(pVar, iVar)) && !Cbs2_VarIsAssigned(p, Gia_ObjFaninId1(pVar, iVar));  } 
static inline int   Cbs2_VarFanin0Value( Cbs2_Man_t * p, Gia_Obj_t * pVar, int iVar ) { return Cbs2_VarIsAssigned(p, Gia_ObjFaninId0(pVar, iVar)) ? (Cbs2_VarValue(p, Gia_ObjFaninId0(pVar, iVar)) ^ Gia_ObjFaninC0(pVar)) : 2;   }
static inline int   Cbs2_VarFanin1Value( Cbs2_Man_t * p, Gia_Obj_t * pVar, int iVar ) { return Cbs2_VarIsAssigned(p, Gia_ObjFaninId1(pVar, iVar)) ? (Cbs2_VarValue(p, Gia_ObjFaninId1(pVar, iVar)) ^ Gia_ObjFaninC1(pVar)) : 2;   }
*/
 
static inline int   Cbs2_VarMark0( Cbs2_Man_t * p, int iVar )                      { return Vec_StrEntry(&p->vMark, iVar);              }
static inline void  Cbs2_VarSetMark0( Cbs2_Man_t * p, int iVar, int Value )        { Vec_StrWriteEntry(&p->vMark, iVar, (char)Value);   } 
 
//static inline int   Cbs2_VarMark0( Cbs2_Man_t * p, int iVar )                      { return Vec_StrEntry(&p->vAssign, iVar) >= 2;       }
//static inline void  Cbs2_VarSetMark0( Cbs2_Man_t * p, int iVar, int Value )        { Vec_StrWriteEntry(&p->vAssign, iVar, (char)(2^Vec_StrEntry(&p->vAssign, iVar)));   } 
 
static inline int   Cbs2_VarIsAssigned( Cbs2_Man_t * p, int iVar )                 { return Vec_StrEntry(&p->vAssign, iVar) < 2;        }
static inline void  Cbs2_VarUnassign( Cbs2_Man_t * p, int iVar )                   { assert( Cbs2_VarIsAssigned(p, iVar)); Vec_StrWriteEntry(&p->vAssign, iVar, (char)(2+Vec_StrEntry(&p->vAssign, iVar))); Cbs2_VarSetUnused(p, iVar); }
 
static inline int   Cbs2_VarValue( Cbs2_Man_t * p, int iVar )                      { return Vec_StrEntry(&p->vAssign, iVar);            }
static inline void  Cbs2_VarSetValue( Cbs2_Man_t * p, int iVar, int v )            { assert( !Cbs2_VarIsAssigned(p, iVar)); Vec_StrWriteEntry(&p->vAssign, iVar, (char)v);                                  }
 
static inline int   Cbs2_VarIsJust( Cbs2_Man_t * p, Gia_Obj_t * pVar, int iVar )      { return Gia_ObjIsAnd(pVar) && !Cbs2_VarIsAssigned(p, Gia_ObjFaninId0(pVar, iVar)) && !Cbs2_VarIsAssigned(p, Gia_ObjFaninId1(pVar, iVar));  } 
static inline int   Cbs2_VarFanin0Value( Cbs2_Man_t * p, Gia_Obj_t * pVar, int iVar ) { return Cbs2_VarValue(p, Gia_ObjFaninId0(pVar, iVar)) ^ Gia_ObjFaninC0(pVar);   }
static inline int   Cbs2_VarFanin1Value( Cbs2_Man_t * p, Gia_Obj_t * pVar, int iVar ) { return Cbs2_VarValue(p, Gia_ObjFaninId1(pVar, iVar)) ^ Gia_ObjFaninC1(pVar);   }
 
 
static inline int   Cbs2_VarDecLevel( Cbs2_Man_t * p, int iVar )                   { assert( !Cbs2_VarUnused(p, iVar) ); return Vec_IntEntry(&p->vLevReason, 3*iVar);    }
static inline int   Cbs2_VarReason0( Cbs2_Man_t * p, int iVar )                    { assert( !Cbs2_VarUnused(p, iVar) ); return Vec_IntEntry(&p->vLevReason, 3*iVar+1);  }
static inline int   Cbs2_VarReason1( Cbs2_Man_t * p, int iVar )                    { assert( !Cbs2_VarUnused(p, iVar) ); return Vec_IntEntry(&p->vLevReason, 3*iVar+2);  }
static inline int * Cbs2_VarReasonP( Cbs2_Man_t * p, int iVar )                    { assert( !Cbs2_VarUnused(p, iVar) ); return Vec_IntEntryP(&p->vLevReason, 3*iVar+1); }
//static inline int   Cbs2_ClauseDecLevel( Cbs2_Man_t * p, int hClause )             { return Cbs2_VarDecLevel( p, p->pClauses.pData[hClause] );                           }
 
static inline int   Cbs2_ClauseSize( Cbs2_Man_t * p, int hClause )                 { return p->pClauses.pData[hClause];                                                  }
static inline int * Cbs2_ClauseLits( Cbs2_Man_t * p, int hClause )                 { return p->pClauses.pData+hClause+1;                                                 }
static inline int   Cbs2_ClauseLit( Cbs2_Man_t * p, int hClause, int i )           { return p->pClauses.pData[hClause+1+i];                                              }
static inline int * Cbs2_ClauseNext1p( Cbs2_Man_t * p, int hClause )               { return p->pClauses.pData+hClause+Cbs2_ClauseSize(p, hClause)+2;                     }
 
static inline void  Cbs2_ClauseSetSize( Cbs2_Man_t * p, int hClause, int x )       { p->pClauses.pData[hClause] = x;                                                     }
static inline void  Cbs2_ClauseSetLit( Cbs2_Man_t * p, int hClause, int i, int x ) { p->pClauses.pData[hClause+i+1] = x;                                                 }
static inline void  Cbs2_ClauseSetNext( Cbs2_Man_t * p, int hClause, int n, int x ){ p->pClauses.pData[hClause+Cbs2_ClauseSize(p, hClause)+1+n] = x;                     }
 
 
#define Cbs2_QueForEachEntry( Que, iObj, i )                         \
    for ( i = (Que).iHead; (i < (Que).iTail) && ((iObj) = (Que).pData[i]); i++ )
 
#define Cbs2_ClauseForEachEntry( p, hClause, iObj, i )               \
    for ( i = 1; i <= Cbs2_ClauseSize(p, hClause) && (iObj = (p)->pClauses.pData[hClause+i]); i++ )
#define Cbs2_ClauseForEachEntry1( p, hClause, iObj, i )                   \
    for ( i = 2; i <= Cbs2_ClauseSize(p, hClause) && (iObj = (p)->pClauses.pData[hClause+i]); i++ )
 
#define Cbs2_ObjForEachFanout( p, iObj, iFanLit )                      \
    for ( iFanLit = Vec_IntEntry(&p->vFanout0, iObj); iFanLit; iFanLit = Vec_IntEntry(&p->vFanoutN, iFanLit) )


void Cbs2_SetDefaultParams( Cbs2_Par_t * pPars )
{
    memset( pPars, 0, sizeof(Cbs2_Par_t) );
    pPars->nBTLimit    =  1000;   // limit on the number of conflicts
    pPars->nJustLimit  =   500;   // 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->fUseFanout  =     1;
    pPars->fVerbose    =     1;   // print detailed statistics
}
void Cbs2_ManSetConflictNum( Cbs2_Man_t * p, int Num )
{
    p->Pars.nBTLimit = Num;
}

Cbs2_Man_t * Cbs2_ManAlloc( Gia_Man_t * pGia )
{
    Cbs2_Man_t * p;
    p = ABC_CALLOC( Cbs2_Man_t, 1 );
    p->pProp.nSize = p->pJust.nSize = p->pClauses.nSize = 10000;
    p->pProp.pData = ABC_ALLOC( int, p->pProp.nSize );
    p->pJust.pData = ABC_ALLOC( int, p->pJust.nSize );
    p->pClauses.pData = ABC_ALLOC( int, p->pClauses.nSize );
    p->pClauses.iHead = p->pClauses.iTail = 1;
    p->vModel   = Vec_IntAlloc( 1000 );
    p->vTemp    = Vec_IntAlloc( 1000 );
    p->pAig     = pGia;
    Cbs2_SetDefaultParams( &p->Pars );
    Vec_StrFill( &p->vAssign,    Gia_ManObjNum(pGia), 2 );
    Vec_StrFill( &p->vMark,      Gia_ManObjNum(pGia), 0 );
    Vec_IntFill( &p->vLevReason, 3*Gia_ManObjNum(pGia), -1 );
    Vec_IntFill( &p->vWatches,   2*Gia_ManObjNum(pGia), 0 );
    Vec_IntFill( &p->vFanout0,   Gia_ManObjNum(pGia),   0 );
    Vec_IntFill( &p->vFanoutN,   2*Gia_ManObjNum(pGia), 0 );
    Vec_IntFill( &p->vActivity,  Gia_ManObjNum(pGia), 0 );
    Vec_IntGrow( &p->vActStore,  1000 );
    Vec_IntGrow( &p->vJStore,    1000 );
    Vec_IntGrow( &p->vWatchUpds, 1000 );
    return p;
}

void Cbs2_ManStop( Cbs2_Man_t * p )
{
    Vec_StrErase( &p->vAssign );
    Vec_StrErase( &p->vMark );
    Vec_IntErase( &p->vLevReason );
    Vec_IntErase( &p->vWatches );
    Vec_IntErase( &p->vFanout0 );
    Vec_IntErase( &p->vFanoutN );
    Vec_IntErase( &p->vActivity );
    Vec_IntErase( &p->vActStore );
    Vec_IntErase( &p->vJStore );
    Vec_IntErase( &p->vWatchUpds );
    Vec_IntFree( p->vModel );
    Vec_IntFree( p->vTemp );
    ABC_FREE( p->pClauses.pData );
    ABC_FREE( p->pProp.pData );
    ABC_FREE( p->pJust.pData );
    ABC_FREE( p );
}

Vec_Int_t * Cbs2_ReadModel( Cbs2_Man_t * p )
{
    return p->vModel;
}
 
 
 

static inline int Cbs2_ManCheckLimits( Cbs2_Man_t * p )
{
    p->nFails[0] += p->Pars.nJustThis > p->Pars.nJustLimit;
    p->nFails[1] += p->Pars.nBTThis > p->Pars.nBTLimit;
    return p->Pars.nJustThis > p->Pars.nJustLimit || p->Pars.nBTThis > p->Pars.nBTLimit;
}

static inline void Cbs2_ManSaveModel( Cbs2_Man_t * p, Vec_Int_t * vCex )
{
    int i, iLit;
    Vec_IntClear( vCex );
    p->pProp.iHead = 0;
    Cbs2_QueForEachEntry( p->pProp, iLit, i )
    {
        int iVar = Abc_Lit2Var(iLit);
        if ( Gia_ObjIsCi(Gia_ManObj(p->pAig, iVar)) )
            Vec_IntPush( vCex, Abc_Var2Lit(Gia_ManIdToCioId(p->pAig, iVar), !Cbs2_VarValue(p, iVar)) );
    }
} 
static inline void Cbs2_ManSaveModelAll( Cbs2_Man_t * p, Vec_Int_t * vCex )
{
    int i, iLit;
    Vec_IntClear( vCex );
    p->pProp.iHead = 0;
    Cbs2_QueForEachEntry( p->pProp, iLit, i )
    {
        int iVar = Abc_Lit2Var(iLit);
        Vec_IntPush( vCex, Abc_Var2Lit(iVar, !Cbs2_VarValue(p, iVar)) );
    }
} 

static inline int Cbs2_QueIsEmpty( Cbs2_Que_t * p )
{
    return p->iHead == p->iTail;
}

static inline void Cbs2_QuePush( Cbs2_Que_t * p, int iObj )
{
    if ( p->iTail == p->nSize )
    {
        p->nSize *= 2;
        p->pData = ABC_REALLOC( int, p->pData, p->nSize ); 
    }
    p->pData[p->iTail++] = iObj;
}
static inline void Cbs2_QueGrow( Cbs2_Que_t * p, int Plus )
{
    if ( p->iTail + Plus > p->nSize )
    {
        p->nSize *= 2;
        p->pData = ABC_REALLOC( int, p->pData, p->nSize ); 
    }
    assert( p->iTail + Plus <= p->nSize );
}

static inline int Cbs2_QueHasNode( Cbs2_Que_t * p, int iObj )
{
    int i, iTemp;
    Cbs2_QueForEachEntry( *p, iTemp, i )
        if ( iTemp == iObj )
            return 1;
    return 0;
}

static inline void Cbs2_QueStore( Cbs2_Que_t * p, int * piHeadOld, int * piTailOld )
{
    int i;
    *piHeadOld = p->iHead;
    *piTailOld = p->iTail;
    for ( i = *piHeadOld; i < *piTailOld; i++ )
        Cbs2_QuePush( p, p->pData[i] );
    p->iHead = *piTailOld;
}

static inline void Cbs2_QueRestore( Cbs2_Que_t * p, int iHeadOld, int iTailOld )
{
    p->iHead = iHeadOld;
    p->iTail = iTailOld;
}
 

static inline int Cbs2_VarFaninFanoutMax( Cbs2_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 );
}

static inline int Cbs2_ManDecideHighest( Cbs2_Man_t * p )
{
    int i, iObj, iObjMax = 0;
    Cbs2_QueForEachEntry( p->pJust, iObj, i )
        if ( iObjMax == 0 || iObjMax < iObj )
            iObjMax = iObj;
    return iObjMax;
}

static inline Gia_Obj_t * Cbs2_ManDecideLowest( Cbs2_Man_t * p )
{
    int i, iObj, iObjMin = 0;
    Cbs2_QueForEachEntry( p->pJust, iObj, i )
        if ( iObjMin == 0 || iObjMin > iObj )
            iObjMin = iObj;
    return Gia_ManObj(p->pAig, iObjMin);
}

static inline Gia_Obj_t * Cbs2_ManDecideMaxFF( Cbs2_Man_t * p )
{
    Gia_Obj_t * pObj, * pObjMax = NULL;
    int i, iMaxFF = 0, iCurFF, iObj;
    assert( p->pAig->pRefs != NULL );
    Cbs2_QueForEachEntry( p->pJust, iObj, i )
    {
        pObj = Gia_ManObj(p->pAig, iObj);
        iCurFF = Cbs2_VarFaninFanoutMax( p, pObj );
        assert( iCurFF > 0 );
        if ( iMaxFF < iCurFF )
        {
            iMaxFF = iCurFF;
            pObjMax = pObj;
        }
    }
    return pObjMax; 
}
 

static inline void Cbs2_ManCancelUntil( Cbs2_Man_t * p, int iBound )
{
    int i, iLit;
    assert( iBound <= p->pProp.iTail );
    p->pProp.iHead = iBound;
    Cbs2_QueForEachEntry( p->pProp, iLit, i )
        Cbs2_VarUnassign( p, Abc_Lit2Var(iLit) );
    p->pProp.iTail = iBound;
}

static inline void Cbs2_ManAssign( Cbs2_Man_t * p, int iLit, int Level, int iRes0, int iRes1 )
{
    int iObj = Abc_Lit2Var(iLit);
    assert( Cbs2_VarUnused(p, iObj) );
    assert( !Cbs2_VarIsAssigned(p, iObj) );
    //Cbs2_VarAssign( p, iObj );
    Cbs2_VarSetValue( p, iObj, !Abc_LitIsCompl(iLit) );
    Cbs2_QuePush( &p->pProp, iLit );
    Vec_IntWriteEntry( &p->vLevReason, 3*iObj,   Level );
    Vec_IntWriteEntry( &p->vLevReason, 3*iObj+1, iRes0 );
    Vec_IntWriteEntry( &p->vLevReason, 3*iObj+2, iRes1 );
}
 
 
 
 
 
 
 
 

static inline void Cbs2_ManPrintClause( Cbs2_Man_t * p, int Level, int hClause )
{
    int i, iLit;
    assert( Cbs2_QueIsEmpty( &p->pClauses ) );
    printf( "Level %2d : ", Level );
    Cbs2_ClauseForEachEntry( p, hClause, iLit, i )
        printf( "%c%d ", Abc_LitIsCompl(iLit) ? '-':'+', Abc_Lit2Var(iLit) );
//        printf( "%d=%d(%d) ", iObj, Cbs2_VarValue(p, Abc_Lit2Var(iLit)), Cbs2_VarDecLevel(p, Abc_Lit2Var(iLit)) );
    printf( "\n" );
}
static inline void Cbs2_ManPrintCube( Cbs2_Man_t * p, int Level, int hClause )
{
    int i, iObj;
    assert( Cbs2_QueIsEmpty( &p->pClauses ) );
    printf( "Level %2d : ", Level );
    Cbs2_ClauseForEachEntry( p, hClause, iObj, i )
        printf( "%c%d ", Cbs2_VarValue(p, iObj)? '+':'-', iObj );
    printf( "\n" );
}
static inline void Cbs2_ManBumpClause( Cbs2_Man_t * p, int hClause )
{
    int i, iObj;
    assert( Cbs2_QueIsEmpty( &p->pClauses ) );
    Cbs2_ClauseForEachEntry( p, hClause, iObj, i )
    {
        //if ( Vec_IntEntry(&p->vActivity, iObj) == 0 )
        //    Vec_IntPush( &p->vActStore, iObj );
        //Vec_IntAddToEntry( &p->vActivity, iObj, 1 );
    }
}
static inline void Cbs2_ManBumpClean( Cbs2_Man_t * p )
{
    int i, iObj;
    Vec_IntForEachEntry( &p->vActStore, iObj, i )
        Vec_IntWriteEntry( &p->vActivity, iObj, 0 );
}

static inline void Cbs2_ManCleanWatch( Cbs2_Man_t * p )
{
    int i, iLit;
    Vec_IntForEachEntry( &p->vWatchUpds, iLit, i )
        Vec_IntWriteEntry( &p->vWatches, iLit, 0 );
    Vec_IntClear( &p->vWatchUpds );
    //Vec_IntForEachEntry( &p->vWatches, iLit, i )
    //    assert( iLit == 0 );
}
static inline void Cbs2_ManWatchClause( Cbs2_Man_t * p, int hClause, int Lit )
{
    int * pLits = Cbs2_ClauseLits( p, hClause );
    int * pPlace = Vec_IntEntryP( &p->vWatches, Abc_LitNot(Lit) );
    if ( *pPlace == 0 )
        Vec_IntPush( &p->vWatchUpds, Abc_LitNot(Lit) );
/*
    if ( pClause->pLits[0] == Lit )
        pClause->pNext0 = p->pWatches[lit_neg(Lit)];  
    else
    {
        assert( pClause->pLits[1] == Lit );
        pClause->pNext1 = p->pWatches[lit_neg(Lit)];  
    }
    p->pWatches[lit_neg(Lit)] = pClause;
*/
    assert( Lit == pLits[0] || Lit == pLits[1] );
    Cbs2_ClauseSetNext( p, hClause, Lit == pLits[1], *pPlace );
    *pPlace = hClause;
}
static inline int Cbs2_QueFinish( Cbs2_Man_t * p, int Level )
{
    Cbs2_Que_t * pQue = &(p->pClauses); 
    int i, iObj, hClauseC, hClause = pQue->iHead, Size = pQue->iTail - pQue->iHead - 1;
    assert( pQue->iHead+1 < pQue->iTail );
    Cbs2_ClauseSetSize( p, pQue->iHead, Size );
    hClauseC = pQue->iHead = pQue->iTail;
    //printf( "Adding cube: " ); Cbs2_ManPrintCube(p, Level, hClause);
    if ( Size == 1 )
        return hClause;
    // create watched clause
    pQue->iHead = hClause;
    Cbs2_QueForEachEntry( p->pClauses, iObj, i )
    {
        if ( i == hClauseC )
            break;
        else if ( i == hClause ) // nlits
            Cbs2_QuePush( pQue, iObj );
        else // literals
            Cbs2_QuePush( pQue, Abc_Var2Lit(iObj, Cbs2_VarValue(p, iObj)) ); // complement
    }
    Cbs2_QuePush( pQue, 0 ); // next0
    Cbs2_QuePush( pQue, 0 ); // next1
    pQue->iHead = pQue->iTail;
    Cbs2_ManWatchClause( p, hClauseC, Cbs2_ClauseLit(p, hClauseC, 0) );
    Cbs2_ManWatchClause( p, hClauseC, Cbs2_ClauseLit(p, hClauseC, 1) );
    //printf( "Adding clause %d: ", hClauseC ); Cbs2_ManPrintClause(p, Level, hClauseC);
    return hClause;
}

static inline int Cbs2_ManDeriveReason( Cbs2_Man_t * p, int Level )
{
    Cbs2_Que_t * pQue = &(p->pClauses);
    int i, k, iObj, iLitLevel, * pReason;
    assert( pQue->pData[pQue->iHead] == 0 );
    assert( pQue->pData[pQue->iHead+1] == 0 );
    assert( pQue->iHead + 2 < pQue->iTail );
    //for ( i = pQue->iHead + 2; i < pQue->iTail; i++ )
    //    assert( !Cbs2_VarMark0(p, pQue->pData[i]) );
    // compact literals
    Vec_IntClear( p->vTemp );
    for ( i = k = pQue->iHead + 2; i < pQue->iTail; i++ )
    {
        iObj = pQue->pData[i];
        if ( Cbs2_VarMark0(p, iObj) ) // unassigned - seen again
            continue;
        //if ( Vec_IntEntry(&p->vActivity, iObj) == 0 )
        //    Vec_IntPush( &p->vActStore, iObj );
        //Vec_IntAddToEntry( &p->vActivity, iObj, 1 );
        // assigned - seen first time
        Cbs2_VarSetMark0(p, iObj, 1);
        Vec_IntPush( p->vTemp, iObj );
        // check decision level
        iLitLevel = Cbs2_VarDecLevel( p, iObj );
        if ( iLitLevel < Level )
        {
            pQue->pData[k++] = iObj;
            continue;
        }
        assert( iLitLevel == Level );
        pReason = Cbs2_VarReasonP( p, iObj );
        if ( pReason[0] == 0 && pReason[1] == 0 ) // no reason
        {
            assert( pQue->pData[pQue->iHead+1] == 0 );
            pQue->pData[pQue->iHead+1] = iObj;
        }
        else if ( pReason[0] != 0 ) // circuit reason
        {
            Cbs2_QuePush( pQue, pReason[0] );
            if ( pReason[1] )
            Cbs2_QuePush( pQue, pReason[1] );
        }
        else // clause reason
        {
            int i, * pLits, nLits = Cbs2_ClauseSize( p, pReason[1] );
            assert( pReason[1] );
            Cbs2_QueGrow( pQue, nLits );
            pLits = Cbs2_ClauseLits( p, pReason[1] );
            assert( iObj == Abc_Lit2Var(pLits[0]) );
            for ( i = 1; i < nLits; i++ )
                Cbs2_QuePush( pQue, Abc_Lit2Var(pLits[i]) );
        }
    }
    assert( pQue->pData[pQue->iHead] == 0 );
    assert( pQue->pData[pQue->iHead+1] != 0 );
    pQue->iTail = k;
    // clear the marks
    Vec_IntForEachEntry( p->vTemp, iObj, i )
        Cbs2_VarSetMark0(p, iObj, 0);
    return Cbs2_QueFinish( p, Level );
}
static inline int Cbs2_ManAnalyze( Cbs2_Man_t * p, int Level, int iVar, int iFan0, int iFan1 )
{
    Cbs2_Que_t * pQue = &(p->pClauses); 
    assert( Cbs2_VarIsAssigned(p, iVar) );
    assert( Cbs2_QueIsEmpty( pQue ) );
    Cbs2_QuePush( pQue, 0 );
    Cbs2_QuePush( pQue, 0 );
    if ( iFan0 ) // circuit conflict
    {
        assert( Cbs2_VarIsAssigned(p, iFan0) );
        assert( iFan1 == 0 || Cbs2_VarIsAssigned(p, iFan1) );
        Cbs2_QuePush( pQue, iVar );
        Cbs2_QuePush( pQue, iFan0 );
        if ( iFan1 )
        Cbs2_QuePush( pQue, iFan1 );
    }
    else // clause conflict
    {
        int i, * pLits, nLits = Cbs2_ClauseSize( p, iFan1 );
        assert( iFan1 );
        Cbs2_QueGrow( pQue, nLits );
        pLits = Cbs2_ClauseLits( p, iFan1 );
        assert( iVar == Abc_Lit2Var(pLits[0]) );
        assert( Cbs2_VarValue(p, iVar) == Abc_LitIsCompl(pLits[0]) );
        for ( i = 0; i < nLits; i++ )
            Cbs2_QuePush( pQue, Abc_Lit2Var(pLits[i]) );
    }
    return Cbs2_ManDeriveReason( p, Level );
}
 

static inline int Cbs2_ManPropagateClauses( Cbs2_Man_t * p, int Level, int Lit )
{
    int i, Value, Cur, LitF = Abc_LitNot(Lit);
    int * pPrev = Vec_IntEntryP( &p->vWatches, Lit );
    //for ( pCur = p->pWatches[Lit]; pCur; pCur = *ppPrev )
    for ( Cur = *pPrev; Cur; Cur = *pPrev )
    {
        int nLits = Cbs2_ClauseSize( p, Cur );
        int * pLits = Cbs2_ClauseLits( p, Cur );
        p->nPropCalls[1]++;
//printf( "  Watching literal %c%d on level %d.\n", Abc_LitIsCompl(Lit) ? '-':'+', Abc_Lit2Var(Lit), Level );
        // make sure the false literal is in the second literal of the clause
        //if ( pCur->pLits[0] == LitF )
        if ( pLits[0] == LitF )
        {
            //pCur->pLits[0] = pCur->pLits[1];
            pLits[0] = pLits[1];
            //pCur->pLits[1] = LitF;
            pLits[1] = LitF;
            //pTemp = pCur->pNext0;
            //pCur->pNext0 = pCur->pNext1;
            //pCur->pNext1 = pTemp;
            ABC_SWAP( int, pLits[nLits], pLits[nLits+1] );
        }
        //assert( pCur->pLits[1] == LitF );
        assert( pLits[1] == LitF );
 
        // if the first literal is true, the clause is satisfied
        //if ( pCur->pLits[0] == p->pAssigns[lit_var(pCur->pLits[0])] )
        if ( Cbs2_VarValue(p, Abc_Lit2Var(pLits[0])) == !Abc_LitIsCompl(pLits[0]) )
        {
            //ppPrev = &pCur->pNext1;
            pPrev = Cbs2_ClauseNext1p(p, Cur);
            continue;
        }
 
        // look for a new literal to watch
        for ( i = 2; i < nLits; i++ )
        {
            // skip the case when the literal is false
            //if ( lit_neg(pCur->pLits[i]) == p->pAssigns[lit_var(pCur->pLits[i])] )
            if ( Cbs2_VarValue(p, Abc_Lit2Var(pLits[i])) == Abc_LitIsCompl(pLits[i]) )
                continue;
            // the literal is either true or unassigned - watch it
            //pCur->pLits[1] = pCur->pLits[i];
            //pCur->pLits[i] = LitF;
            pLits[1] = pLits[i];
            pLits[i] = LitF;
            // remove this clause from the watch list of Lit
            //*ppPrev = pCur->pNext1;
            *pPrev = *Cbs2_ClauseNext1p(p, Cur);
            // add this clause to the watch list of pCur->pLits[i] (now it is pCur->pLits[1])
            //Intb_ManWatchClause( p, pCur, pCur->pLits[1] );
            Cbs2_ManWatchClause( p, Cur, Cbs2_ClauseLit(p, Cur, 1) );
            break;
        }
        if ( i < nLits ) // found new watch
            continue;
 
        // clause is unit - enqueue new implication
        //if ( Inta_ManEnqueue(p, pCur->pLits[0], pCur) )
        //{
        //    ppPrev = &pCur->pNext1;
        //    continue;
        //}
 
        // clause is unit - enqueue new implication
        Value = Cbs2_VarValue(p, Abc_Lit2Var(pLits[0]));
        if ( Value >= 2 ) // unassigned
        {
            Cbs2_ManAssign( p, pLits[0], Level, 0, Cur );
            pPrev = Cbs2_ClauseNext1p(p, Cur);
            continue;
        }
 
        // conflict detected - return the conflict clause
        //return pCur;
        if ( Value == Abc_LitIsCompl(pLits[0]) )
        {
            p->nClauseConf++;
            return Cbs2_ManAnalyze( p, Level, Abc_Lit2Var(pLits[0]), 0, Cur );
        }
    }
    return 0;
}
 

static inline int Cbs2_ManResolve( Cbs2_Man_t * p, int Level, int hClause0, int hClause1 )
{
    Cbs2_Que_t * pQue = &(p->pClauses);
    int i, iObj, LevelMax = -1, LevelCur;
    assert( pQue->pData[hClause0+1] != 0 );
    assert( pQue->pData[hClause0+1] == pQue->pData[hClause1+1] );
    //Cbs2_ClauseForEachEntry1( p, hClause0, iObj, i )
    //    assert( !Cbs2_VarMark0(p, iObj) );
    //Cbs2_ClauseForEachEntry1( p, hClause1, iObj, i )
    //    assert( !Cbs2_VarMark0(p, iObj) );
    assert( Cbs2_QueIsEmpty( pQue ) );
    Cbs2_QuePush( pQue, 0 );
    Cbs2_QuePush( pQue, 0 );
//    for ( i = hClause0 + 1; (iObj = pQue->pData[i]); i++ )
    Cbs2_ClauseForEachEntry1( p, hClause0, iObj, i )
    {
        if ( Cbs2_VarMark0(p, iObj) ) // unassigned - seen again
            continue;
        //if ( Vec_IntEntry(&p->vActivity, iObj) == 0 )
        //    Vec_IntPush( &p->vActStore, iObj );
        //Vec_IntAddToEntry( &p->vActivity, iObj, 1 );
        // assigned - seen first time
        Cbs2_VarSetMark0(p, iObj, 1);
        Cbs2_QuePush( pQue, iObj );
        LevelCur = Cbs2_VarDecLevel( p, iObj );
        if ( LevelMax < LevelCur )
            LevelMax = LevelCur;
    }
//    for ( i = hClause1 + 1; (iObj = pQue->pData[i]); i++ )
    Cbs2_ClauseForEachEntry1( p, hClause1, iObj, i )
    {
        if ( Cbs2_VarMark0(p, iObj) ) // unassigned - seen again
            continue;
        //if ( Vec_IntEntry(&p->vActivity, iObj) == 0 )
        //    Vec_IntPush( &p->vActStore, iObj );
        //Vec_IntAddToEntry( &p->vActivity, iObj, 1 );
        // assigned - seen first time
        Cbs2_VarSetMark0(p, iObj, 1);
        Cbs2_QuePush( pQue, iObj );
        LevelCur = Cbs2_VarDecLevel( p, iObj );
        if ( LevelMax < LevelCur )
            LevelMax = LevelCur;
    }
    for ( i = pQue->iHead + 2; i < pQue->iTail; i++ )
        Cbs2_VarSetMark0(p, pQue->pData[i], 0);
    return Cbs2_ManDeriveReason( p, LevelMax );
}

static inline int Cbs2_ManPropagateOne( Cbs2_Man_t * p, int iVar, int Level )
{
    Gia_Obj_t * pVar = Gia_ManObj( p->pAig, iVar ); int Value0, Value1;
    assert( !Gia_IsComplement(pVar) );
    assert( Cbs2_VarIsAssigned(p, iVar) );
    if ( Gia_ObjIsCi(pVar) )
        return 0;
    p->nPropCalls[0]++;
    assert( Gia_ObjIsAnd(pVar) );
    Value0 = Cbs2_VarFanin0Value(p, pVar, iVar);
    Value1 = Cbs2_VarFanin1Value(p, pVar, iVar);
    if ( Cbs2_VarValue(p, iVar) == 1 )
    { // value is 1
        if ( Value0 == 0 || Value1 == 0 ) // one is 0
        {
            if ( Value0 == 0 && Value1 != 0 )
                return Cbs2_ManAnalyze( p, Level, iVar, Gia_ObjFaninId0(pVar, iVar), 0 );
            if ( Value0 != 0 && Value1 == 0 )
                return Cbs2_ManAnalyze( p, Level, iVar, Gia_ObjFaninId1(pVar, iVar), 0 );
            assert( Value0 == 0 && Value1 == 0 );
            return Cbs2_ManAnalyze( p, Level, iVar, Gia_ObjFaninId0(pVar, iVar), Gia_ObjFaninId1(pVar, iVar) );
        }
        if ( Value0 >= 2 ) // first is unassigned
            Cbs2_ManAssign( p, Gia_ObjFaninLit0(pVar, iVar), Level, iVar, 0 );
        if ( Value1 >= 2 ) // first is unassigned
            Cbs2_ManAssign( p, Gia_ObjFaninLit1(pVar, iVar), Level, iVar, 0 );
        return 0;
    }
    // value is 0
    if ( Value0 == 0 || Value1 == 0 ) // one is 0
        return 0;
    if ( Value0 == 1 && Value1 == 1 ) // both are 1
        return Cbs2_ManAnalyze( p, Level, iVar, Gia_ObjFaninId0(pVar, iVar), Gia_ObjFaninId1(pVar, iVar) );
    if ( Value0 == 1 || Value1 == 1 ) // one is 1 
    {
        if ( Value0 >= 2 ) // first is unassigned
            Cbs2_ManAssign( p, Abc_LitNot(Gia_ObjFaninLit0(pVar, iVar)), Level, iVar, Gia_ObjFaninId1(pVar, iVar) );
        if ( Value1 >= 2 ) // second is unassigned
            Cbs2_ManAssign( p, Abc_LitNot(Gia_ObjFaninLit1(pVar, iVar)), Level, iVar, Gia_ObjFaninId0(pVar, iVar) );
        return 0;
    }
    assert( Cbs2_VarIsJust(p, pVar, iVar) );
    //assert( !Cbs2_QueHasNode( &p->pJust, iVar ) );
    if ( !p->Pars.fUseFanout )
        Cbs2_QuePush( &p->pJust, iVar );
    return 0;
}

static inline int Cbs2_ManPropagateTwo( Cbs2_Man_t * p, int iVar, int Level )
{
    Gia_Obj_t * pVar = Gia_ManObj( p->pAig, iVar ); int Value0, Value1;
    assert( !Gia_IsComplement(pVar) );
    assert( Gia_ObjIsAnd(pVar) );
    assert( Cbs2_VarIsAssigned(p, iVar) );
    assert( Cbs2_VarValue(p, iVar) == 0 );
    Value0 = Cbs2_VarFanin0Value(p, pVar, iVar);
    Value1 = Cbs2_VarFanin1Value(p, pVar, iVar);
    p->nPropCalls[1]++;
    // value is 0
    if ( Value0 == 0 || Value1 == 0 ) // one is 0
        return 0;
    if ( Value0 == 1 && Value1 == 1 ) // both are 1
        return Cbs2_ManAnalyze( p, Level, iVar, Gia_ObjFaninId0(pVar, iVar), Gia_ObjFaninId1(pVar, iVar) );
    assert( Value0 == 1 || Value1 == 1 );
    if ( Value0 >= 2 ) // first is unassigned
        Cbs2_ManAssign( p, Abc_LitNot(Gia_ObjFaninLit0(pVar, iVar)), Level, iVar, Gia_ObjFaninId1(pVar, iVar) );
    if ( Value1 >= 2 ) // first is unassigned
        Cbs2_ManAssign( p, Abc_LitNot(Gia_ObjFaninLit1(pVar, iVar)), Level, iVar, Gia_ObjFaninId0(pVar, iVar) );
    return 0;
}

static inline void Cbs2_ManPropagateUnassigned( Cbs2_Man_t * p, int iVar, int Level )
{
    Gia_Obj_t * pVar = Gia_ManObj( p->pAig, iVar ); int Value0, Value1;
    assert( !Gia_IsComplement(pVar) );
    assert( Gia_ObjIsAnd(pVar) );
    assert( !Cbs2_VarIsAssigned(p, iVar) );
    Value0 = Cbs2_VarFanin0Value(p, pVar, iVar);
    Value1 = Cbs2_VarFanin1Value(p, pVar, iVar);
    p->nPropCalls[2]++;
    if ( Value0 == 0 && Value1 == 0 ) // the output becomes 1
        Cbs2_ManAssign( p, Abc_Var2Lit(iVar, 1), Level, Gia_ObjFaninId0(pVar, iVar), Gia_ObjFaninId1(pVar, iVar) );
    else if ( Value0 == 0 ) // the output becomes 0
        Cbs2_ManAssign( p, Abc_Var2Lit(iVar, 1), Level, Gia_ObjFaninId0(pVar, iVar), 0 );
    else if ( Value1 == 0 ) // the output becomes 0
        Cbs2_ManAssign( p, Abc_Var2Lit(iVar, 1), Level, Gia_ObjFaninId1(pVar, iVar), 0 );
    else if ( Value0 == 1 && Value1 == 1 ) // the output becomes 1
        Cbs2_ManAssign( p, Abc_Var2Lit(iVar, 0), Level, Gia_ObjFaninId0(pVar, iVar), Gia_ObjFaninId1(pVar, iVar) );
}

int Cbs2_ManPropagate( Cbs2_Man_t * p, int Level )
{
    while ( 1 )
    {
        int i, k, iVar, iLit, hClause;
        Cbs2_QueForEachEntry( p->pProp, iLit, i )
        {
            if ( (hClause = Cbs2_ManPropagateOne( p, Abc_Lit2Var(iLit), Level )) )
                return hClause;
        }
        p->pProp.iHead = p->pProp.iTail;
        k = p->pJust.iHead;
        Cbs2_QueForEachEntry( p->pJust, iVar, i )
        {
            if ( Cbs2_VarIsJust(p, Gia_ManObj(p->pAig, iVar), iVar) )
                p->pJust.pData[k++] = iVar;
            else if ( (hClause = Cbs2_ManPropagateTwo( p, iVar, Level )) )
                return hClause;
        }
        if ( k == p->pJust.iTail )
            break;
        p->pJust.iTail = k;
    }
    return 0;
}
 
 
int Cbs2_ManPropagate2( Cbs2_Man_t * p, int Level )
{
    int i, iLit, iFan, hClause;
    Cbs2_QueForEachEntry( p->pProp, iLit, i )
    {
        if ( (hClause = Cbs2_ManPropagateClauses(p, Level, iLit)) )
            return hClause;
        Cbs2_ObjForEachFanout( p, Abc_Lit2Var(iLit), iFan )
        {
            int iFanout = Abc_Lit2Var(iFan);
            if ( !Cbs2_VarIsAssigned(p, iFanout) )
                Cbs2_ManPropagateUnassigned( p, iFanout, Level );
            else if ( (hClause = Cbs2_ManPropagateOne(p, iFanout, Level)) )
                return hClause;
        }
        if ( (hClause = Cbs2_ManPropagateOne( p, Abc_Lit2Var(iLit), Level )) )
            return hClause;
    }
    p->pProp.iHead = p->pProp.iTail;
    return 0;
}
 

static inline int Cbs2_ManUpdateDecVar2( Cbs2_Man_t * p, int iObj, int iDecLit )
{
    Gia_Obj_t * pObj = Gia_ManObj(p->pAig, iObj); int iFan;
 
    iFan = Gia_ObjFaninId0(pObj, iObj);
    if ( iDecLit == -1 || Gia_ObjLevelId(p->pAig, Abc_Lit2Var(iDecLit)) < Gia_ObjLevelId(p->pAig, iFan) )
        iDecLit = Abc_LitNot(Gia_ObjFaninLit0(pObj, iObj));
 
    iFan = Gia_ObjFaninId1(pObj, iObj);
    if ( iDecLit == -1 || Gia_ObjLevelId(p->pAig, Abc_Lit2Var(iDecLit)) < Gia_ObjLevelId(p->pAig, iFan) )
        iDecLit = Abc_LitNot(Gia_ObjFaninLit1(pObj, iObj));
 
    return iDecLit;
}
static inline int Cbs2_ManUpdateDecVar3( Cbs2_Man_t * p, int iObj, int iDecLit )
{
    Gia_Obj_t * pObj = Gia_ManObj(p->pAig, iObj); int iFan;
 
    iFan = Gia_ObjFaninId0(pObj, iObj);
    if ( iDecLit == -1 || Vec_IntEntry(&p->vActivity, Abc_Lit2Var(iDecLit)) < Vec_IntEntry(&p->vActivity, iFan) )
        iDecLit = Abc_LitNot(Gia_ObjFaninLit0(pObj, iObj));
 
    iFan = Gia_ObjFaninId1(pObj, iObj);
    if ( iDecLit == -1 || Vec_IntEntry(&p->vActivity, Abc_Lit2Var(iDecLit)) < Vec_IntEntry(&p->vActivity, iFan) )
        iDecLit = Abc_LitNot(Gia_ObjFaninLit1(pObj, iObj));
 
    return iDecLit;
}
static inline int Cbs2_ManUpdateDecVar( Cbs2_Man_t * p, int iObj, int iDecLit )
{
    Gia_Obj_t * pObj = Gia_ManObj(p->pAig, iObj); int iFan;
 
    iFan = Gia_ObjFaninId0(pObj, iObj);
    if ( iDecLit == -1 || Gia_ObjRefNumId(p->pAig, Abc_Lit2Var(iDecLit)) < Gia_ObjRefNumId(p->pAig, iFan) )
        iDecLit = Abc_LitNot(Gia_ObjFaninLit0(pObj, iObj));
 
    iFan = Gia_ObjFaninId1(pObj, iObj);
    if ( iDecLit == -1 || Gia_ObjRefNumId(p->pAig, Abc_Lit2Var(iDecLit)) < Gia_ObjRefNumId(p->pAig, iFan) )
        iDecLit = Abc_LitNot(Gia_ObjFaninLit1(pObj, iObj));
 
    return iDecLit;
}
int Cbs2_ManUpdateFrontier( Cbs2_Man_t * p, int iPropHeadOld, int * piDecLit )
{
    abctime clk = Abc_Clock();
    int i, iVar, iLit, iJustTailOld = p->pJust.iTail;
    *piDecLit = -1;
    assert( Cbs2_QueIsEmpty(&p->pProp) );
    // visit old frontier nodes
    Cbs2_QueForEachEntry( p->pJust, iVar, i )
        if ( i == iJustTailOld )
            break;
        else if ( Cbs2_VarIsJust(p, Gia_ManObj(p->pAig, iVar), iVar) )
        {
            Cbs2_QuePush( &p->pJust, iVar );
            //*piDecLit = Cbs2_ManUpdateDecVar( p, iVar, *piDecLit );
        }
    // append new nodes
    p->pProp.iHead = iPropHeadOld;
    Cbs2_QueForEachEntry( p->pProp, iLit, i )
    {
        iVar = Abc_Lit2Var(iLit);
        if ( Cbs2_VarIsJust(p, Gia_ManObj(p->pAig, iVar), iVar) )
        {
            Cbs2_QuePush( &p->pJust, iVar );
            //*piDecLit = Cbs2_ManUpdateDecVar( p, iVar, *piDecLit );
        }
    }
    p->pProp.iHead = p->pProp.iTail;
    // update the head of the frontier
    p->pJust.iHead = iJustTailOld;
    // return 1 if the queue is empty
    p->timeJFront += Abc_Clock() - clk;
//printf( "%d ", p->pJust.iTail - p->pJust.iHead );
    return Cbs2_QueIsEmpty(&p->pJust);
}

 
int Cbs2_ManSolve1_rec( Cbs2_Man_t * p, int Level )
{ 
    Gia_Obj_t * pVar;
    Cbs2_Que_t * pQue = &(p->pClauses);
    int iPropHead, iJustHead, iJustTail;
    int hClause, hLearn0, hLearn1, iVar, iDecLit;
    // propagate assignments
    assert( !Cbs2_QueIsEmpty(&p->pProp) );
    if ( (hClause = Cbs2_ManPropagate( p, Level )) )
        return hClause;
    // check for satisfying assignment
    assert( Cbs2_QueIsEmpty(&p->pProp) );
    if ( Cbs2_QueIsEmpty(&p->pJust) )
        return 0;
    // quit using resource limits
    p->Pars.nJustThis = Abc_MaxInt( p->Pars.nJustThis, p->pJust.iTail - p->pJust.iHead );
    if ( Cbs2_ManCheckLimits( p ) )
        return 0;
    // remember the state before branching
    iPropHead = p->pProp.iHead;
    Cbs2_QueStore( &p->pJust, &iJustHead, &iJustTail );
    // find the decision variable
    assert( p->Pars.fUseHighest );
    iVar = Cbs2_ManDecideHighest( p );
    pVar = Gia_ManObj( p->pAig, iVar );
    assert( Cbs2_VarIsJust(p, pVar, iVar) );
    // chose decision variable using fanout count
    if ( Gia_ObjRefNum(p->pAig, Gia_ObjFanin0(pVar)) > Gia_ObjRefNum(p->pAig, Gia_ObjFanin1(pVar)) )
        iDecLit = Abc_LitNot(Gia_ObjFaninLit0(pVar, iVar));
    else
        iDecLit = Abc_LitNot(Gia_ObjFaninLit1(pVar, iVar));
    // decide on first fanin
    Cbs2_ManAssign( p, iDecLit, Level+1, 0, 0 );
    if ( !(hLearn0 = Cbs2_ManSolve1_rec( p, Level+1 )) )
        return 0;
    if ( pQue->pData[hLearn0+1] != Abc_Lit2Var(iDecLit) )
        return hLearn0;
    Cbs2_ManCancelUntil( p, iPropHead );
    Cbs2_QueRestore( &p->pJust, iJustHead, iJustTail );
    // decide on second fanin
    Cbs2_ManAssign( p, Abc_LitNot(iDecLit), Level+1, 0, 0 );
    if ( !(hLearn1 = Cbs2_ManSolve1_rec( p, Level+1 )) )
        return 0;
    if ( pQue->pData[hLearn1+1] != Abc_Lit2Var(iDecLit) )
        return hLearn1;
    hClause = Cbs2_ManResolve( p, Level, hLearn0, hLearn1 );
    Cbs2_ManBumpClause( p, hClause );
//    Cbs2_ManPrintCube( p, Level, hClause );
//    if ( Level > Cbs2_ClauseDecLevel(p, hClause) )
//        p->Pars.nBTThisNc++;
    p->Pars.nBTThis++;
    return hClause;
}
 
int Cbs2_ManSolve2_rec( Cbs2_Man_t * p, int Level )
{ 
    Gia_Obj_t * pVar;
    Cbs2_Que_t * pQue = &(p->pClauses);
    int iPropHead, iJustHead, iJustTail;
    int hClause, hLearn0, hLearn1, iVar, iDecLit, iDecLit2;
    int iPropHeadOld = p->pProp.iHead;
    // propagate assignments
    assert( !Cbs2_QueIsEmpty(&p->pProp) );
    if ( (hClause = Cbs2_ManPropagate2( p, Level )) )
        return hClause;
    // check for satisfying assignment
    assert( Cbs2_QueIsEmpty(&p->pProp) );
//    if ( Cbs2_QueIsEmpty(&p->pJust) )
//        return 0;
    if ( Cbs2_ManUpdateFrontier(p, iPropHeadOld, &iDecLit2) )
        return 0;
    // quit using resource limits
    p->Pars.nJustThis = Abc_MaxInt( p->Pars.nJustThis, p->pJust.iTail - p->pJust.iHead );
    if ( Cbs2_ManCheckLimits( p ) )
        return 0;
    // remember the state before branching
    iPropHead = p->pProp.iHead;
//    Cbs2_QueStore( &p->pJust, &iJustHead, &iJustTail );
    iJustHead = p->pJust.iHead;
    iJustTail = p->pJust.iTail;
    // find the decision variable
 
    assert( p->Pars.fUseHighest );
    iVar = Cbs2_ManDecideHighest( p );
    pVar = Gia_ManObj( p->pAig, iVar );
    assert( Cbs2_VarIsJust(p, pVar, iVar) );
    // chose decision variable using fanout count
    if ( Gia_ObjRefNum(p->pAig, Gia_ObjFanin0(pVar)) > Gia_ObjRefNum(p->pAig, Gia_ObjFanin1(pVar)) )
//    if ( Vec_IntEntry(&p->vActivity, Gia_ObjFaninId0(pVar, iVar)) > Vec_IntEntry(&p->vActivity, Gia_ObjFaninId1(pVar, iVar)) )
        iDecLit = Abc_LitNot(Gia_ObjFaninLit0(pVar, iVar));
    else
        iDecLit = Abc_LitNot(Gia_ObjFaninLit1(pVar, iVar));
 
    //iDecLit = iDecLit2;
 
    // decide on first fanin
    Cbs2_ManAssign( p, iDecLit, Level+1, 0, 0 );
    if ( !(hLearn0 = Cbs2_ManSolve2_rec( p, Level+1 )) )
        return 0;
    if ( pQue->pData[hLearn0+1] != Abc_Lit2Var(iDecLit) )
        return hLearn0;
    Cbs2_ManCancelUntil( p, iPropHead );
    Cbs2_QueRestore( &p->pJust, iJustHead, iJustTail );
    // decide on second fanin
    Cbs2_ManAssign( p, Abc_LitNot(iDecLit), Level+1, 0, 0 );
    if ( !(hLearn1 = Cbs2_ManSolve2_rec( p, Level+1 )) )
        return 0;
    if ( pQue->pData[hLearn1+1] != Abc_Lit2Var(iDecLit) )
        return hLearn1;
    hClause = Cbs2_ManResolve( p, Level, hLearn0, hLearn1 );
    Cbs2_ManBumpClause( p, hClause );
    //Cbs2_ManPrintCube( p, Level, hClause );
//    if ( Level > Cbs2_ClauseDecLevel(p, hClause) )
//        p->Pars.nBTThisNc++;
    p->Pars.nBTThis++;
    return hClause;
}
 
int Cbs2_ManSolve_rec( Cbs2_Man_t * p, int Level )
{ 
    return p->Pars.fUseFanout ? Cbs2_ManSolve2_rec(p, Level) : Cbs2_ManSolve1_rec(p, Level);
}

int Cbs2_ManSolve( Cbs2_Man_t * p, int iLit )
{
    int RetValue = 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;
    Cbs2_ManAssign( p, iLit, 0, 0, 0 );
    if ( !Cbs2_ManSolve_rec(p, 0) && !Cbs2_ManCheckLimits(p) )
        Cbs2_ManSaveModel( p, p->vModel );
    else
        RetValue = 1;
    Cbs2_ManCancelUntil( p, 0 );
    Cbs2_ManCleanWatch( p );
    Cbs2_ManBumpClean( p );
    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 ( Cbs2_ManCheckLimits( p ) )
        RetValue = -1;
    return RetValue;
}
int Cbs2_ManSolve2( Cbs2_Man_t * p, int iLit, int iLit2 )
{
    int RetValue = 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;
    Cbs2_ManAssign( p, iLit, 0, 0, 0 );
    if ( iLit2 ) 
    Cbs2_ManAssign( p, iLit2, 0, 0, 0 );
    if ( !Cbs2_ManSolve_rec(p, 0) && !Cbs2_ManCheckLimits(p) )
        Cbs2_ManSaveModelAll( p, p->vModel );
    else
        RetValue = 1;
    Cbs2_ManCancelUntil( p, 0 );
    Cbs2_ManCleanWatch( p );
    Cbs2_ManBumpClean( p );
    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 ( Cbs2_ManCheckLimits( p ) )
        RetValue = -1;
    return RetValue;
}

void Cbs2_ManSatPrintStats( Cbs2_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 );
}

void Cbs2_ObjPrintFanouts( Cbs2_Man_t * p, int iObj )
{
    int iFanLit;
    printf( "Fanouts of node %d: ", iObj );
    Cbs2_ObjForEachFanout( p, iObj, iFanLit )
        printf( "%d ", Abc_Lit2Var(iFanLit) );
    printf( "\n" );
}
 
void Cbs2_ManPrintFanouts( Cbs2_Man_t * p )
{
    Gia_Obj_t * pObj; int iObj;
    Gia_ManForEachObj( p->pAig, pObj, iObj )
        if ( Vec_IntEntry(&p->vFanout0, iObj) )
            Cbs2_ObjPrintFanouts( p, iObj );
}
void Cbs2_ObjCreateFanout( Cbs2_Man_t * p, int iObj, int iFan0, int iFan1 )
{
    Vec_IntWriteEntry( &p->vFanoutN, Abc_Var2Lit(iObj, 0), Vec_IntEntry(&p->vFanout0, iFan0) );
    Vec_IntWriteEntry( &p->vFanoutN, Abc_Var2Lit(iObj, 1), Vec_IntEntry(&p->vFanout0, iFan1) );
    Vec_IntWriteEntry( &p->vFanout0, iFan0, Abc_Var2Lit(iObj, 0) );
    Vec_IntWriteEntry( &p->vFanout0, iFan1, Abc_Var2Lit(iObj, 1) );
}
void Cbs2_ObjDeleteFanout( Cbs2_Man_t * p, int iObj )
{
    Vec_IntWriteEntry( &p->vFanoutN, Abc_Var2Lit(iObj, 0), 0 );
    Vec_IntWriteEntry( &p->vFanoutN, Abc_Var2Lit(iObj, 1), 0 );
    Vec_IntWriteEntry( &p->vFanout0, iObj, 0 );
}
void Cbs2_ManCreateFanout_rec( Cbs2_Man_t * p, int iObj )
{
    Gia_Obj_t * pObj; int iFan0, iFan1;
    if ( !iObj || Gia_ObjIsTravIdCurrentId(p->pAig, iObj) )
        return;
    Gia_ObjSetTravIdCurrentId(p->pAig, iObj);
    pObj = Gia_ManObj(p->pAig, iObj);
    if ( Gia_ObjIsCi(pObj) )
        return;
    assert( Gia_ObjIsAnd(pObj) );
    iFan0 = Gia_ObjFaninId0(pObj, iObj);
    iFan1 = Gia_ObjFaninId1(pObj, iObj);
    Cbs2_ManCreateFanout_rec( p, iFan0 );
    Cbs2_ManCreateFanout_rec( p, iFan1 );
    Cbs2_ObjCreateFanout( p, iObj, iFan0, iFan1 ); 
}
void Cbs2_ManDeleteFanout_rec( Cbs2_Man_t * p, int iObj )
{
    Gia_Obj_t * pObj = Gia_ManObj(p->pAig, iObj); int iFan0, iFan1;
    Cbs2_ObjDeleteFanout( p, iObj ); 
    if ( Gia_ObjIsCi(pObj) )
        return;
    assert( Gia_ObjIsAnd(pObj) );
    iFan0 = Gia_ObjFaninId0(pObj, iObj);
    iFan1 = Gia_ObjFaninId1(pObj, iObj);
    if ( Vec_IntEntry(&p->vFanout0, iFan0) )  Cbs2_ManDeleteFanout_rec( p, iFan0 );
    if ( Vec_IntEntry(&p->vFanout0, iFan1) )  Cbs2_ManDeleteFanout_rec( p, iFan1 );
}
void Cbs2_ManCheckFanouts( Cbs2_Man_t * p )
{
    Gia_Obj_t * pObj;
    int iObj;
    Gia_ManForEachObj( p->pAig, pObj, iObj )
    {
        assert( Vec_IntEntry(&p->vFanout0, iObj) == 0 );
        assert( Vec_IntEntry(&p->vFanoutN, Abc_Var2Lit(iObj, 0)) == 0 );
        assert( Vec_IntEntry(&p->vFanoutN, Abc_Var2Lit(iObj, 1)) == 0 );
    }
}

Vec_Int_t * Cbs2_ManSolveMiterNc( Gia_Man_t * pAig, int nConfs, Vec_Str_t ** pvStatus, int fVerbose )
{
    extern void Gia_ManCollectTest( Gia_Man_t * pAig );
    extern void Cec_ManSatAddToStore( Vec_Int_t * vCexStore, Vec_Int_t * vCex, int Out );
    Cbs2_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_ManLevelNum( 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 = Cbs2_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      = Cbs2_ReadModel( p );
    // solve for each output
    Gia_ManForEachCo( pAig, pRoot, i )
    {
        //printf( "\nOutput %d\n", i );
 
        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;
 
        Gia_ManIncrementTravId( pAig );
        Cbs2_ManCreateFanout_rec( p, Gia_ObjFaninId0p(pAig, pRoot) );
        //Cbs2_ManPrintFanouts( p );
 
        status = Cbs2_ManSolve( p, Gia_ObjFaninLit0p(pAig, pRoot) );
        //printf( "\n" );
 
        Cbs2_ManDeleteFanout_rec( p, Gia_ObjFaninId0p(pAig, pRoot) );
        //Cbs2_ManCheckFanouts( p );
 
/*
        if ( status == -1 )
        {
            p->Pars.fUseHighest = 0;
            p->Pars.fUseLowest  = 1;
            status = Cbs2_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 )
        {
            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 )
        Cbs2_ManSatPrintStats( p );
    if ( fVerbose )
    {
//    printf( "RecCalls = %8d.  RecClause = %8d.  RecNonChro = %8d.\n", p->nRecCall, p->nRecClause, p->nRecNonChro );
    printf( "Prop1 = %d.  Prop2 = %d.  Prop3 = %d.  ClaConf = %d.   FailJ = %d.  FailC = %d.   ", p->nPropCalls[0], p->nPropCalls[1], p->nPropCalls[2], p->nClauseConf, p->nFails[0], p->nFails[1] );
    Abc_PrintTime( 1, "JFront", p->timeJFront );
    }
 
    Cbs2_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;
}
 

 
 
ABC_NAMESPACE_IMPL_END