#ifndef CA_UWATERLOO_ALUMNI_DWHARDER_BINARY_TREE
#define CA_UWATERLOO_ALUMNI_DWHARDER_BINARY_TREE

// Author:  Douglas Wilhelm Harder
// Copyright (c) 2011 by Douglas Wilhelm Harder.  All rights reserved.

namespace Data_structures {
	template <typename Type>
	class Binary_tree {
		protected:
			Binary_node<Type> *root_node;

		public:
			Binary_tree();

			virtual Binary_node<Type> *root() const;

			bool empty() const;
			int size() const;
			int height() const;
	};

	template <typename Type>
	Binary_tree<Type>::Binary_tree():
	root_node( 0 ) {
		// Empty constructor
	}

	template <typename Type>
	bool Binary_tree<Type>::empty() const {
		return ( root_node == 0 );
	}

	template <typename Type>
	int Binary_tree<Type>::size() const {
		return ( root() == 0 ) ? 0 : root()->size();
	}

	template <typename Type>
	int Binary_tree<Type>::height() const {
		return ( root() == 0 ) ? -1 : root()->height();
	}
}

#endif