小代码

/********************
* http://anycodes.cn/zh/ **********************/
#include <stdio.h>
#include <stdlib.h>
#include <iostream>
#include <stdio.h>
#include <string.h>
#include <queue>
#include <math.h>
using namespace std;

#define OK 1
#define ERROR 0
#define LINK 0
#define THREAD 1

//the type of data
typedef char DataType;
typedef int Status;

//keep the information of node
typedef struct BiThrNode
{
DataType data;
struct BiThrNode *lChild,*rChild;
int lTag,rTag;
}BiThrNode,*BiThrTree;
BiThrTree pre = NULL;
char ss[]="123#####";int i=0;
//CBFEDA//
//preorder the tree
Status createBiTree(BiThrTree *T)
{
char ch; //scanf("%c",&ch);
ch=ss[i++];
if(ch == '\n'|| ch == '\t')
{
return OK;
}

if(ch == '#') *T = NULL;
else
{
*T = (BiThrNode *)malloc(sizeof(BiThrNode));
(*T)->data = ch;
(*T)->rTag = LINK;
(*T)->lTag = LINK;
createBiTree(&(*T)->lChild);
createBiTree(&(*T)->rChild);
}
return OK;
}
void InThreading(BiThrTree t)
{
if(t)
{
InThreading(t->lChild);

cout<<" [ "<<t->lTag<<" ] "<<t->data<<" [ "<<t->rTag<<" ] ";
if(!t->lChild)
{
t->lTag = THREAD;
t->lChild = pre;
}
if(!t->rChild)
{
pre->rTag = THREAD;
pre->rChild = t;
}
pre = t;
InThreading(t->rChild);
}
}

Status InOrderThreading(BiThrTree *Thrt,BiThrTree T)
{  *Thrt = (BiThrTree)malloc(sizeof(BiThrNode));
(*Thrt)->lTag = LINK;
(*Thrt)->rTag = THREAD;
(*Thrt)->rChild = *Thrt;
if(!T)
{
(*Thrt)->lChild = *Thrt;
}
else
{
(*Thrt)->lChild = T;
pre = *Thrt;

InThreading(T);
pre->rChild = *Thrt;
pre->rTag = THREAD;
(*Thrt)->rChild = pre;
}

return OK;
}
void lay(BiThrTree root,int n)                         /*/ 层次打印 /*/
{  //assert(root)
int kk=n;
while(kk--)
{
int k=1; int m=1;int i=0;
BiThrTree b=root;
queue<BiThrTree> q;
q.push(b);
while(!q.empty())
{
b=q.front();  if(b->lChild) q.push(b->lChild); if(b->rChild) q.push(b->rChild);
m=pow(2,k-1); for(i=0;i<n/2;i++) cout<<" ";cout<<b->data; q.pop();
while(--m)
{
for(i=0;i<2*(n/2)+1;i++) cout<<" ";
if(!q.empty())
{ b=q.front();
if(b->lChild) q.push(b->lChild);
if(b->rChild) q.push(b->rChild);
cout<<b->data; q.pop();
}
else cout<<"#";
}
cout<<endl;
n=n/2;
k++;
}
}
}

int main()
{
BiThrTree base = NULL,thrdBase = NULL;
createBiTree(&base);
InOrderThreading(&thrdBase,base);
//lay(thrdBase,2);
return 0;
}
/***** OUT PUT*************
[ 0 ] 3 [ 0 ]  [ 0 ] 2 [ 0 ]  [ 0 ] 1 [ 0 ]
？？
**********************/