二叉树基本操作C代码

#include<stdio.h>  
#include<malloc.h>  
#define LEN sizeof(struct ChainTree)  
struct ChainTree  
{  
    int num;  
    struct ChainTree *left;  
    struct ChainTree *right;  
};  
/*函数功能：进行查找操作。*/  
ChainTree *BinTreeFind(ChainTree *bt,int data)//在二叉树中查找值为data的结点。  
{  
    ChainTree *p;  
    if(bt==NULL)  
        return NULL;  
    else  
    {  
        if(bt->num==data)  
        return bt;  
        else{  
            if(p=BinTreeFind(bt->left,data))  
                return p;  
             else if(p=BinTreeFind(bt->right,data))  
                 return p;  
             else  
                 return NULL;  
          }  
    }  
}  
/*函数功能：先序遍历。*/  
void BinTree_DLR(ChainTree *bt)  
{  
    if(bt)  
    {  
        printf("%d",bt->num);  
        if(bt->left)  
        {  
            BinTree_DLR(bt->left);  
        }  
        if(bt->right)  
        {  
            BinTree_DLR(bt->right);  
        }  
    }  
    return;  
}  
/*函数定义：后序遍历。*/  
void BinTree_LRD(ChainTree *bt)  
{  
    if(bt)  
    {  
        BinTree_LRD(bt->left);  
        BinTree_LRD(bt->right);  
        printf("%d",bt->num);  
    }  
    return;  
}  
/*函数功能：中序遍历。*/  
void BinTree_LDR(ChainTree *bt)  
{  
    if(bt)  
    {  
        BinTree_LDR(bt->left);  
        printf("%d",bt->num);  
        BinTree_LDR(bt->right);  
    }  
    return;  
}  
/*函数功能初始化一个二叉树，建立根节点。*/  
ChainTree *InitRoot()  
{  
    ChainTree *node;  
    node=(struct ChainTree*)malloc(LEN);  
    printf("请输入根节点的值：");  
    scanf("%d",&node->num);  
    node->left=NULL;  
    node->right=NULL;  
    return node;  
}  
  
/*添加数据到二叉树*/  
int BinTreeAddNode(ChainTree *bt,ChainTree *node,int n)  
{  
    if(bt==NULL)  
    {  
        printf("
父结点不在，请先设置父结点。");  
        return 0;  
    }  
    switch(n)  
    {  
        case 1:  
            if(bt->left)  
            {  
                printf("左子树结点不为空。");  
                return 0;  
            }  
            else  
                bt->left=node;  
            break;  
        case 2:  
            if(bt->right)  
            {  
                printf("右子树结点不为空。");  
                return 0;  
            }  
            else  
                bt->right=node;  
            break;  
            default:  
                printf("参数错误！
");  
            return 0;   
    }  
    return 1;  
}  
  
/*函数功能：添加结点到二叉树。*/  
void AddNode(ChainTree *bt)  
{  
    int data;  
    int select;  
    ChainTree *node,*parent;  
    node=(struct ChainTree*)malloc(LEN);  
    printf("
输入二叉树结点数据");  
    scanf("%d",&node->num);  
    node->left=NULL;  
    node->right=NULL;  
    printf("
输入父结点数据：");  
    scanf("%d",&data);  
    parent=BinTreeFind(bt,data);  
    if(!parent)  
    {  
        printf("
未找到父结点。");  
    }  
    printf("
1.添加到左子树
2.添加到右子树
");  
    do{  
        scanf("%d",&select);  
        if(select==1||select==2)  
        BinTreeAddNode(parent,node,select);  
        }while(select!=1&&select!=2);  
}  
  
/*求二叉树叶子结点个数*/  
void CountLeaf(ChainTree *bt,int &count)  
{  
    if(bt)  
    {  
        if((!bt->left)&&(!bt->right))  
            count++;  
        CountLeaf(bt->left,count);  
        CountLeaf(bt->right,count);  
    }  
}  
  
/*求二叉树深度*/  
int BinTreeDepth(ChainTree *bt)  
{  
    int dep1,dep2;  
    if(bt==NULL)  
    return 0;  
    else  
    {  
        dep1=BinTreeDepth(bt->left);                //左子树深度（递归调用）  
        dep2=BinTreeDepth(bt->right);              //右子树深度（递归调用）  
        if(dep1>dep2)  
            return dep1+1;  
        else  
            return dep2+1;  
    }  
}  
  
int main()  
{  
    struct ChainTree *p1,*p2,*head,*p3;  
    int select = 1000;  
    int countleaf=0;                                        //该变量计算叶子结点个数  
    while(select!=0){  
        printf("
1.设置二叉树根元素
2.添加二叉树根节点
3.先序遍历
4.中序遍历
5.后序遍历
6.输出叶子结点个数
7.求二叉树深度
0.退出");  
        scanf("%d",&select);  
        switch(select)  
        {  
        case 1:  
            head=InitRoot();  
            break;  
        case 2:  
            AddNode(head);  
            break;  
        case 3:  
            BinTree_DLR(head);  
            break;  
        case 4:  
             BinTree_LDR(head);  
             break;  
        case 5:  
            BinTree_LRD(head);  
            break;  
        case 6:  
               countleaf=0;                                              //求二叉树叶子结点数  
            CountLeaf(head,countleaf);  
            printf("
%d",countleaf);  
            break;  
        case 7:  
            printf("二叉树深度为:%d
",BinTreeDepth(head));  
             break;  
        case 0:  
            select = 0;  
            break;  
        }  
    }  
}