类成员的指针必须NULL化，否则是乱七八糟的东西

 

class BiTree

{

    public:

        BiTree();

        virtual ~BiTree();

        virtual void insertNode(Node * newNode);

        virtual void deleteNode(Node * delNode);

        virtual void searchNode(VALUETYPE value)

        {

        }

        virtual int getDepth();

        virtual int getWidth()

        {

            travelwide();

            return 0;

        }

        virtual void SetTreeDraw();

        friend ostream& operator << (ostream&,BiTree&);

    protected:

    private:

        Node * root=NULL;

        TreeDrawing mytreedraw;

        QQueue<Node> tempque;

        QQueue<Node> resultque;

        virtual void leftrotate(Node * mynode){}

        virtual void rightrotate(Node * mynode){}

        virtual void transplant(Node * oldnode, Node * newnode);

        virtual Node * tree_min(Node * mynode);

        virtual Node * tree_max(Node * mynode);

       // virtual QPoint GetNodesLocation(Node * curnode);

        virtual void print(Node * mynode);

        virtual int traveldeep(Node * node, int layer,int line);

        virtual void traveldeep(Node * node,void (* callback)(Node * node));

        virtual int travelwide();

};