二叉树［C实现］

#include<stdio.h>
#include<malloc.h>
#include<iostream>

//定义节点
typedef struct BiNode{
        char data;
        struct BiNode *lch;
        struct BiNode *rch;
}BiNode,*BiTree;

//先序拓展序列建立二叉树
void Create(BiTree &T)
{
        T =(BiNode*) malloc (sizeof(BiNode));
       
        printf("Enter the data \n");
        scanf(" %c",&T->data);
        if(T->data=='#') T = NULL;
        if(T){
                printf("");
                Create(T->lch);
                Create(T->rch);
        }
}

//先序遍历 (递归)
void Preorder (BiTree T)
{                   
   if (T) {
      printf(" %c",T->data);             // 访问根结点
     
      Preorder(T->lch); // 遍历左子树
      Preorder(T->rch);// 遍历右子树
   }
}

//中序遍历 （递归）
void Inorder (BiTree T)
{
     if(T) {
       Inorder(T->lch);
      
       printf(" %c",T->data);
      
       Inorder(T->rch);   
       }
}

//后序遍历 （递归）
void Postorder (BiTree T)
{
     if(T) {
       Postorder(T->lch);
       Postorder(T->rch);
      
       printf(" %c",T->data);
     }
}

int main()
{
    //建树
    printf("The fuction Create() is called.\n");
    BiTree T;
    Create(T);
   
    //三种遍历递归算法
    printf("\n");   
    printf("The fuction Preorder() is called.\n");
    Preorder(T);
   
    printf("\n");
    printf("The fuction Inorder() is called.\n");
    Inorder(T);
   
    printf("\n");
    printf("The fuction Postorder() is called.\n");
    Postorder(T);
   
   
    printf("\n");
    system("pause");
   
}