template<class T>
 void BinTree<T>::PreOrder(BinTreeNode<T>*subTree){
 //前序遍历以subTree为根的树
     if(subTree!=NULL){
         cout<<subTree->data<<endl;
         PreOrder(subTree->leftChild);
         PreOrder(subTree->rightChild);
     }
 } 

 template<class T>
 void BinTree<T>::InOrder(BinTreeNode<T>*subTree){
 //中序遍历以subTree为根的树
     if(subTree!=NULL){//NULL是递归终止条件
         InOrder(subTree->leftChild);//中序遍历左子树
         cout<<subTree->data<<endl;//访问根结点
         InOrder(subTree->rightChild);//中序遍历右子树
     }
 }

 template<class T>
 void BinTree<T>::PostOrder(BinTreeNode<T>*subTree){
 //后序遍历以subtree为根的树
     if(subTree!=NULL){
         PostOrder(subTree->leftChild);
         PostOrder(subTree->rightChild);
         cout<<subTree->data<<endl;
     }
 } 

 template<class T>
 void BinTree<T>::LevelOrder(BinTreeNode<T>*subTree) {
 //层次序遍历以subTree为根的二叉树
     Queue<BinTreeNode<T>*>Q;//定义队列
     BinTreeNode<T>*p=subTree;
     Q.EnQueue(p);//根结点入队
     while(!Q.IsEmpty()){//队列不空
         Q.DeQueue(p);
         cout<<p->data;
         if(p->leftChild!=NULL) Q.EnQueue(p->leftChild);//左子入队
         if(p->rightChild!=NULL) Q.EnQueue(p->rightChild);//右子入队
     }
 }

 template<class T>
 BinTree<T>::BinTree(const BinTree<T>&s){
 //复制构造函数
     root=Copy(s.root);
 }
 template<class T>
 BinTreeNode<T>* BinTree<T>::Copy(BinTreeNode<T>*orignode){
 //返回一个指针，它给出一个以orignode为根的二叉树的副本
     if(orignode==NULL) return NULL;
     BinTreeNode<T>*temp=new BinTreeNode<T>;//创建根结点
     temp->data=orignode->data;
     temp->leftChild=Copy(orignode->leftChild);
     temp->rightChild=Copy(orignode->rightChild);
     return temp;
 } 

 template<class T>
 bool equal(BinTreeNode<T>*a,BinTreeNode<T>*b){
 //为BinTree类的友元函数
     if(a==NULL&&b==NULL) return true;
     if(a!=NULL&&b!=NULL&&a->data==b->data&&equal(a->leftChild,b->leftChild)&&equal(a->rightChild,b->rightChild)) return true;
     else return false;
 }

 约定以输入序列中不可能出现的值作为空结点的值以结束递归，此值在RefValue中，如#
 template<class T>
 void BinTree<T>::CreatBinTree(ifstream& in,BinTreeNode<T>*&subTree){
 //以递归的方式建立二叉树
     T item;
     if(!in.eof()){//未读完，读入并建树
         in>>item;
         if(item!=RefValue){
             subTree->data=item;
             CreatBinTree(in,subTree->leftChild);//递归建立左子树
             CreatBinTree(in,subTree->rightChild);//递归建立右子树
         }
         else subTree=NULL;
     }
 } 

 template<class T>
 int BinTree<T>::Size(BinTreeNode<T>*subTree) const{
 //计算以subTree为根的二叉树的结点的个数
     ;//递归结束
     +Size(subTree->leftChild)+Size(subTree->rightChild);
 } 

 template<class T>
 int BinTree<T>::Height(BinTreeNode<T>*subTree) const{
 //计算以subTree为根的二叉树的高度
     ;
     +max(Height(subTree->leftChild),Height(subTree->rightChild));
 }