【数据结构】迭代器实现二叉树的中序遍历

迭代器

template<class T,class Ref,class Ptr>
struct __TreeIterator
{
	typedef BinTreeNode<T> Node;
	typedef __TreeIterator<T,Ref,Ptr> Self;
	__TreeIterator()
	{}
	__TreeIterator(Node* node)
		:_node(node)
	{}
	Ref operator*()
	{
		assert(_node);
		return _node->_date;
	}
	Self& operator++()
	{
		assert(_node);
		if(_node->RightTag==Link)
		{
			Node* right=_node->rightchild;
			while (right&&right->LeftTag==Link)
			{
				right=right->leftchild;
			}
			_node=right;
		}
		else
		{
			_node=_node->rightchild;
		}
		return *this;
	}
	Self& operator++(int)
	{
		Self tmp(*this);
		++(*this);
		return tmp;
	}
	Self& operator--()
	{
		assert(_node);
		if(_node->LeftTag=Link)
		{
			Node* left=_node->leftchild;
			while (left&&left->RightTag==Link)
			{
				left=left->rightchild;
			}
			_node=left;
		}
		else
		{
			_node=_node->leftchild;
		}
		return *this;
	}
	bool o