private BstNode< type>*root Type revalue BstNode<Type>* lastfound void Make Empty( BstNode< Type>*& ptr) void Insert( const Type & x, bstNode< type>*& ptr void Remove(const Type &x, BstNode< type>*& ptr) BstNode< Type>* Find( const Type &x BstNode< type>* ptr )const BstNode<Type>* Min( Bstnode< type>* ptr )const BstNode< type>* max( bstNode< type>* ptr)const friend class BSTIterator< Type 2021222 202021/2/22 20 private: BstNode<Type> * root ; Type RefValue ; BstNode<Type> * lastfound ; void MakeEmpty( BstNode<Type> * & ptr ) ; void Insert( const Type & x , BstNode<Type> * & ptr ); void Remove(const Type & x , BstNode<Type> * & ptr ) ; BstNode<Type> * Find( const Type & x , BstNode<Type> * ptr ) const ; BstNode<Type> * Min( BstNode<Type> * ptr ) const ; BstNode<Type> * Max( BstNode<Type> * ptr ) const ; friend class BSTIterator<Type> ; }