//---- public makeEmpty  ( ) -----
template <class Comparable>
void BST<Comparable>::makeEmtpy ( )
{
   // just call private method
   makeEmpty ( root );
}



//---- private makeEmpty ( ) ------
template <class Comparable>
void BST<Comparable>::
makeEmpty ( BinaryNode<Comparable> * & t )
{
   if ( t != NULL )
   {
      makeEmpty ( t->left );
      makeEmpty ( t->right );
      delete t;
   }
}