树的抽象数据类型 template <class Type>class Tree i public ee e(); position root o; Buildroot( const Type& value ) position First Child( position position Nextsibling( position p, position v ) position Parent( position ) Type Retrieve( position p ) position Insertchild( const position p, const Type &valuetemplate <class Type> class Tree { public: Tree ( ); ~Tree ( ); position Root ( ); BuildRoot ( const Type& value ); position FirstChild ( position p ); position NextSibling ( position p, position v ); position Parent ( position p ); Type Retrieve ( position p ); position InsertChild ( const position p, const Type &value ); 树的抽象数据类型