#include<iostream.h>
#include<iomanip.h>
#include<malloc.h>
#include<stdio.h>
#include<stdlib.h>
#include<stdafx.h>
#define OVERFLOW -1
#define ERROR 0
#define OK 1
typedef struct BiTNode{//注意采用的是二叉链表作为二叉树的存储结构
    TElemType data;
    struct BiTNode*lchild,*rchild;
}BiTNode,*BiTree;

Status CreateBiTree_PreOrder(BiTree&T){//先序次序构造二叉树
    TElemType ch;
    scanf("%c",&ch);
    if(ch=='')T=NULL;
    else{
        if(!(T=(BiTNode*)malloc(sizeof(BiTNode))) exit(OVERFLOW);
        T->data=ch;
        CreateBiTree_PreOrder(T->lchild);
        CreateBiTree-PrOrder(T->rchild);
    }
    return OK;
}
Status PreOrderTraverse(BiTree T,Status(*Visit)(TElemType e)){//先序遍历
    if((*Visit)(T->data))
        if(PreOrderTraverse(T->lchild,Visit))
            if(PreOrderTraverse(T->rchild,Visit))
                return OK;
            return ERROR;
}
return OK;
}

Status InOrderTraverse(BiTree T,Status(*Visit)(TElemType e)){//中序遍历
    if(T!=NULL){
        if(InOrderTraverse(T-lchild,Visit))
            if((*Visit)(T->data))
                if(InOrderTraverse(T->rchild,Visit))
                    return OK;
                return ERROR;
                }
    else return OK;
}

Status PostOrderTraverse(BiTree T,Status(*Visit)(TElemType e)){//后序遍历
    if(T!=NULL){
        if(PostOrderTraverse(T->lchild,Visit))
            if(PostOrderTraverse(T->rchild,Visit))
                if((*Visit)(T->data))
                    return ERROR;
                }
    else return OK;
}
Status Disp(TElemType e){//输出各结点的数据值
    printf("%3c",e);
    return OK;
}
void main()
{BiTree T;
CreateBiTree_PreOrder(&T);
printf("/n");
PreOrderTraverse(T,Disp);
printf("/n");
InOrderTraverse(T,Disp);
printf("/n");
PostOrderTraverse(T,Disp);
printf("/n");
}