C++ TreeNode::TraceDown方法代码示例

TreeNode *BStar::GetBestOptPrb(TreeNode *parent)
{
	double MaxValue = 0.0;
	double PrbD = 0.0;
	TreeNode *aux = 0;
	TreeNode *Sel = 0;

	int DPV = 0; // depth PV
	int DOpt = 0;
	for(aux = parent->SelectBestReal();aux; aux = aux->SelectBestReal())
	{
		DPV++;
	}


	double np = parent->SubtreeSize;
	const double Cucb = 2.0; //0.0000001; //2000.0;

	for(aux = parent->MoveTo(FIRSTCHILD);
		aux; aux = aux->MoveTo(NEXTSIBBLING))
	{
		PrbD = aux->OptPrb ;
		if(	PrbD > MaxValue	)
		{
			MaxValue = PrbD; 
			Sel = aux ;
		}
	}
	
	// PV can not be shorter than opt path
	if(Sel == NULL) Sel = parent->SelectBestReal();
	aux = Sel->TraceDown(1);
	for(;aux && aux != TreeNode::GetRootNode(); aux = aux->MoveTo(PARENT))
		DOpt++;
	if(DOpt > DPV)
		return parent->SelectBestReal();
	return Sel;
}

void BStar::Search()
{
	int Cancelar = 0;
	int i,NExpandFD = 0;
	int LastIteration = -1;
	Cancelar = 0;
	DumpTree *dt;
	TreeNode *CurNode = NULL;		// last move expanded
	TreeNode *CurBestNode = NULL;	// last best
	if(DumpData)
	{
		dt = new DumpTree();
	}

	TreeNode *a = NULL;
	TreeNode *SelectedNode = NULL;
	ColorRoot = TreeNode::GetRootNode()->Color;

	NExpandFD = 18;
	for(i=1;i < FixedDepth;i++)
	{
		NExpandFD *= 3; // Branch factor 3
	}
	if(FixedDepth)
	{
		SelectNodes = (NExpandFD * 6)/10;
		VerifyNodes = NExpandFD - SelectNodes;
	}

	for(;;)
	{
		if(LastIteration == TotalExpand)
			break;						// avoid cicle without expands.
		LastIteration = TotalExpand;
		if(Cancel||Cancelar)
			break;
//		printf("SELECT Step %d\n",TotalExpand);
		while (GetRealValBestAtRoot() <= OptValAnyOtherMoveAtRoot())
		{
			if(BestMoveAtRoot != CurBestNode)
			{
				if(CurBestNode != NULL)
					PrintPV();
				CurBestNode = BestMoveAtRoot;
				LastChange = TotalExpand;
				PrintPV();
			}
			if(TreeNode::GetRootNode()->RealVal > (MATE-50)
				|| TreeNode::GetRootNode()->RealVal < (50-MATE)
				)
			{
				Cancelar= 1;
				// switch to verify
				break;
			}


			TargetVal = ((BestMoveAtRoot->RealVal) + OptVal2ndBest)/2;
			
			// it is unlikely that any other move can achieve as good a RealVal ?
			if( SecondRootOptPrb() < MinAct)
			{
				if(GetRealValBestAtRoot() >= (RealVal2ndBstMoveAtRoot() + 1))
//					goto salida;
				break;
			}
			if(DumpData )
			{
				dt->Print("SELECT STEP Color %d Best %d Target Value %d\n",ColorRoot,BestMoveAtRoot->RealVal,TargetVal);
				dt->Write();
			}
//			Select Root Node with greatest OptPrb;
			a = GetBestOptPrb(TreeNode::GetRootNode());
			if(!a)
				break;
			if(a != CurNode)
			{
				CurNode = a;
			}
//			Trace down the child subtree selecting
//			For Player-to-Move nodes, child with largest OptPrb
//			For Opponent-to-Move nodes, child with best RealVal
//			Until arriving at a leaf node;
			SelectedNode = a->TraceDownNotStopper(true);
			if(DumpData)
			{
				dt->Print("Selected node:");
				dt->DumpPath(SelectedNode,TreeNode::GetRootNode());
				dt->Print("Color root %d\n",TreeNode::GetRootNode()->Color);
				dt->DumpRoot();
			}
			if(SelectedNode->MoveCount != 0) // already expanded, mate pos?
			{
				break;
			}
//			Get RealVal for each Child Node of this leaf;
//			If it is a Player-to-Move node get OptVals for each Child;
			if(Cancelar||Cancel)
				break;
			Expand(SelectedNode,PLAYER);
//.........这里部分代码省略.........