关于二叉树的问题！求解答！

数据结构书随便找一本就有递归建树的例子。。。

template <class T>
struct BTnode
{
     T d;
     BTnode *LTree;
     BTnode *RTree;
};
template <class T>
class BinaryTree
{
private:
     BTnode<T> *BT;
public:
     BinaryTree(){ BT = NULL; }
     ~BinaryTree();
     void CreateBT(T end);
     void PreTravBT();
};
template <class T>
void BinaryTree<T>::CreateBT(T end)
{
     cout<<"please input any value end by -1"<<endl;
     T x;
     cin>>x;
     if(x==end)return;
     BTnode<T> *p;
     p = new BTnode<T>;
     p->d = x;
     p->LTree = NULL;
     p->RTree = NULL;
     BT = p;
     create_bt(p,1,end);
     create_bt(p,2,end);
     cout<<"creae is success"<<endl;
}
template <class T>
BinaryTree<T>::~BinaryTree()
{
     BTnode<T> *p;
     p = BT;
     delete_bt(p);
     cout<<"delete is success"<<endl;
}
template <class T>
static void delete_bt(BTnode<T> *p)
{
     if(p==NULL)return;
     delete_bt(p->LTree);
     delete_bt(p->RTree);
     delete [] p;
}
template <class T>
static void create_bt(BTnode<T> *p,int k,T end)
{
     T x;
     cin>>x;
     if(x==end)return;
     BTnode<T> *q;
     q = new BTnode<T>;
     q->d = x;
     q->LTree = NULL;
     q->RTree = NULL;
     if(k==1)
     {
         p->LTree = q;
     };
     if(k==2)
     {
         p->RTree = q;
     };
     create_bt(q,1,end);
     create_bt(q,2,end);
    
     return;
}
template <class T>
void BinaryTree<T>::PreTravBT()
{
     BTnode<T> *p;
     p = BT;
     pretrav_bt(p);
     cout<<"pretrav_bt is success"<<endl;
}
template <class T>
static void pretrav_bt(BTnode<T> *p)
{
     if(p==NULL)return;
     cout<<p->d<<'\t';
     pretrav_bt(p->LTree);
     pretrav_bt(p->RTree);
     cout<<endl;
     return;
}
不知道几年前写的

实现.cpp
#include <iostream>
#include "bt.h"
using namespace std;
void main(void)
{
     BinaryTree<int> bt;
     bt.CreateBT(-1);
     bt.PreTravBT();
     return;
}