#include<iostream.h>
#include"SeqQueue.cpp"
template<class Type>
struct BinTreeNode{
    Type data;
    BinTreeNode<Type> * leftChild, * rightChild;
    BinTreeNode():leftChild(NULL),rightChild(NULL){}
    BinTreeNode(Type x,BinTreeNode<Type> * l = NULL,BinTreeNode<Type> * r = NULL)
        :data(x),leftChild(l),rightChild(r){}
};

template<class Type>
class BinaryTree{
    public:
        BinaryTree():root(NULL){}
        BinaryTree(Type value):ReValue(value),root(NULL){}
        ~BinaryTree(){destory(root);}
        bool IsEmpty(){return(root==NULL)?true:false;}
        BinTreeNode<Type>*Parent(BinTreeNode<Type>*current){return(root==NULL||root==current)?NULL:Parent(root,current);}//返回父节点
        BinTreeNode<Type>*LeftChild(BinTreeNode<Type>*current){return(current!=NULL)?current->leftChild:NULL;}//返回左子女
        BinTreeNode<Type>*RightChild(BinTreeNode<Type>*current){return(current!=NULL)?current->rightChild:NULL;}//返回右子女
        int Height(){return Size(root);}
        BinTreeNode<Type>*getRoot()const{return root;}
        void preOrder(void(*visit)(BinTreeNode<Type>*p)){PreOrder(root,visit);}//前序
        void inOrder(void(*visit)(BinTreeNode<Type>*p)){InOrder(root,visit);}//中序遍历
        void postOrder(void(*visit)(BinTreeNode<Type>*p)){PostOrder(root,visit);}//后续遍历
        void levelOrder(void(*visit)(BinTreeNode<Type>*p));//层序
    //    int Insert(const Type&item);//插入新元素
    //    BinTreeNode<Type>*Find(Type&item)const;//搜索
        void CreateBinTree(ifstream& in,BinTreeNode<Type>*&subTree);//文件读入建树
        void printBTree(BinTreeNode<Type>*BT);
    protected:
        BinTreeNode<Type>*root;//根指针
        Type RefValue;         //数据停止标志
        int Height(BinTreeNode<Type>*subTree);
        int Size(BinTreeNode<Type>*subTree)const;
        void PreOrder(BinTreeNode<Type>*subTree,void(*visit)(BinTreeNode<Type>*p));
        void InOrder(BinTreeNode<Type>*subTree,void(*visit)(BinTreeNode<Type>*p));
        void PostOrder(BinTreeNode<Type>*subTree,void(*visit)(BinTreeNode<Type>*p));
    //    bool Insert(BinTreeNode<Type>*&subTree,const T&x);
        void destory(BinTreeNode<Type>*subTree);
    //    bool Find(BinTreeNode<Type>*subTree,const T&x)const;
    //    BinTreeNode<Type>*Copy(BinTreeNode<Type>*orignode);
    //    BinTreeNode<Type>*Parent(BinTreeNode<Type>*subTree,BinTreeNode<T>*current);
    //    BinTreeNode<Type>*Find(BinTreeNode<Type>*subTree,const T& x)const;

    //    friend istream& operator>>(istream& in,BinaryTree<T>&Tree);
    //    friend ostream& operator<<(ostream& out,BinaryTree<T>&Tree);
};
template<class Type>
void BinaryTree<Type>::CreateBinTree(ifstream& in,BinTreeNode<Type>*&subTree)
{
    T item;
    if(!in.eof()){
        in>>item;
        if(item!=RefValue){
            subTree=new BinTreeNode<Type>(item);
            if(subTree==NULL)
            {cerr<<"存储分配错误！"<<endl;exit(1);}
            CreateBinTree(in,subTree->leftChild);
            CreateBinTree(in,subTree->rightChild);
        }
        else subTree=NULL;
    }
}
template<class Type>
void BinaryTree<Type>::printBTree(BinTreeNode<Type>*BT){
    if(BT!=NULL){
        cout<<BT->data;
        if(BT->leftChild!=NULL||BT->rightChild!=NULL)
            cout<<'(';
            PrintBTree(BT->leftChild);
            cout<<',';
            if(BT->rightChild!=NULL)
                PrintBTree(BT->rightChild);
            cout<<')';
    }
}
template<class Type>
void BinaryTree<Type>::PostOrder(BinTreeNode<Type>*subTree,void(*visit)(BinTreeNode<Type>*p)){
    if(subTree!=NULL){
        visit(subTree);
        cout<<subTree->data<<endl;
        PreOrder(subTree->leftChild,visit);
        PreOrder(subTree->rightChild,visit);
    }
}
template<class Type>
void BinaryTree<Type>::InOrder(BinTreeNode<Type>*subTree,void(*visit)(BinTreeNode<Type>*p)){
    if(subTree!=NULL){
        InOrder(subTree->leftChild,visit);
        visit(subTree);
        cout<<subTree->data<<endl;
        InOrder(subTree->rightChild,visit);
    }
}
template<class Type>
void BinaryTree<Type>::PostOrder(BinTreeNode<Type>*subTree,void(*visit)(BinTreeNode<Type>*p)){
    if(subTree!=NULL){
        PostOrder(subTree->leftChild,visit);
        PostOrder(subTree->rightChild,visit);
        visit(subTree);
        cout<<subTree->data<<endl;
    }
}
template<class Type>
void BinaryTree<Type>::levelOrder(void(*visit)(BinTreeNode<Type>*p)){
    SeqQueue<BinTreeNode<Type>*> Q;
    BinTreeNode<Type> *p=root;
    Q.EnQueue(p);
    while(!Q.IsEmpty()){
        Q.DeQueue(p);visit(p);
        if(p->leftChild!=NULL)
            Q.EnQueue(p->leftChild);
        if(p->rightChild!=NULL)
            Q.EnQueue(p->rightChild);
    }
   
}
//私有函数计算以*subTree为根二叉树的结点个数
template<class Type>
int BinaryTree<Type>::Size(BinTreeNode<Type> *subTree)const{
    if(subTree==NULL)
        return 0;
    else
        return (1+Size(subTree->leftChild)+Size(subTree->rightChild));
}
/*私有函数计算以*subTree 为根的二叉树的深度
template<class Type>
int BinaryTree<Type>::Height(BinTreeNode<Type> *subTree)const{
    if(subTree==NULL)return 0;
    else{
        int i=Height(subTree->leftChild);
        int j=Height(subTree->rightChild);
        return(i<j)?j+1:i+1;
    }
}*/
template<class Type>
void BinaryTree<Type>::destory(BinTreeNode<Type>*subTree){
    if(subTree!=NULL){
    destory(subTree->leftChild);
    destory(subTree->rightChild);
    delete subTree;
    }
}

Compiling...
BinaryTree.cpp
d:\c++\5\二叉树\binarytree.cpp(30) : error C2061: syntax error : identifier 'ifstream'
        d:\c++\5\二叉树\binarytree.cpp(49) : see reference to class template instantiation 'BinaryTree<Type>' being compiled
d:\c++\5\二叉树\binarytree.cpp(51) : error C2061: syntax error : identifier 'ifstream'
d:\c++\5\二叉树\binarytree.cpp(105) : error C2995: 'PostOrder' : template function has already been defined
        d:\c++\5\二叉树\binarytree.cpp(39) : see declaration of 'PostOrder'
执行 cl.exe 时出错.