二叉树的线索化 C++代码

#include "stdafx.h"//运行环境visuals studio
#include<iostream>
using namespace std;
typedef enum PointTag{Link,Thread};
typedef struct Node{
char data;
Node*lchild,*rchild;
PointTag LTag,RTag;
}ThrNode,*ThrTree;
static ThrTree pre;
void create(ThrTree &T){
char ch;
cin>>ch;
if(ch=='#')
   T=NULL;
else{
   T=(ThrTree)malloc(sizeof(ThrNode));
   T->data=ch;
   T->LTag=Link;
   T->RTag=Link;
   create(T->lchild);
   create(T->rchild);
}
return;
}
void inThreading(ThrTree p){
if(p){
   inThreading(p->lchild);
   if(p->lchild==NULL){
    p->LTag=Thread;