二叉树

#include<stdio.h>
#include<string.h>
#include<iostream>
#include<malloc.h>
#include<math.h>
using namespace std;
#define MAXSIZE 100
#define OK 1
typedef int Ststus ;
typedef  char  TElemType  ;
typedef struct BiThrNode
{
    TElemType data;
    struct BiThrNode *lchild,*rchild;
}BiThrNode,*BiTree;
//先序建立
void CreateBiTree(BiTree &T)
{
    char ch;
    scanf("%c",&ch);
    T=new BiThrNode;
    if(ch=='#') T=NULL;
    else
    {
        T->data=ch;
        CreateBiTree(T->lchild);
        CreateBiTree(T->rchild);
    }
    return ;
}
//先序遍历
void PreOrder(BiTree T)
{
    if(T)
    {
        cout<<T->data<<" ";
        PreOrder(T->lchild);
        PreOrder(T->rchild);
    }
    else return;

}
//中序遍历
void InOrder(BiTree T)
{
    if(T)
    {
        InOrder(T->lchild);
        cout<<T->data<<" ";
        InOrder(T->rchild);
    }
    else return ;
}
//后序遍历
void PostOrder(BiTree T)
{
    if(T)
    {
        PostOrder(T->lchild);
        PostOrder(T->rchild);
        cout<<T->data<<" ";
    }
    else
       return ;
}

void ClearBiTree(BiTree *T)
{
    if(*T)
    {
      if((*T)->lchild)ClearBiTree(&(*T)->lchild);
      if((*T)->rchild)ClearBiTree(&(*T)->rchild);
      free(T);//%%
      (*T)=NULL;
    }
}
//判断树是否为空
int IsEmpty(BiTree T)
{
    if(T)return 0;
    else return 1;
}
//计算树的深度
int GetDepth(BiTree T)
{
    int l=0,r=0;
    if(T->lchild)
    l=GetDepth(T->lchild);
    else l=0;
    if(T->rchild)
    r=GetDepth(T->rchild);
    else r=0;
    return max(r,l)+1;
}
//查询根节点
TElemType GetRoot(BiTree T)
{
    if(IsEmpty(T))
        return NULL;
    else
        return T->data;
}
//交换左右子树
void Exchange(BiTree T)
{
    BiTree temp = NULL;
    if(T->lchild == NULL && T->rchild == NULL)
        return;
    else
    {
        temp = T->lchild;
        T->lchild = T->rchild;
        T->rchild = temp;
    }
    if(T->lchild)
        Exchange(T->lchild);
    if(T->rchild)
        Exchange(T->rchild);
}

int main()
{
   BiTree  T;
   CreateBiTree(T);
   cout<<"先序遍历"<<endl;
   PreOrder(T);
   cout<<"中序遍历"<<endl;
   InOrder(T);
   cout<<"后序遍历"<<endl;
   PostOrder(T);
    cout<<"树的深度:"<<GetDepth(T)<<endl;
    cout<<"树的根节点:"<<GetRoot(T)<<endl;
    if(IsEmpty(T))
   cout<<"空"<<endl;
   else cout<<"非空"<<endl;
   Exchange(T);
   PreOrder(T);ClearBiTree(&T);
   if(IsEmpty(T))
   cout<<"空"<<endl;
   else cout<<"非空"<<endl;
}