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");

 }