二叉树的基本操作及应用

BTree.h

#ifndef __BTree_H__
#define __BTree_H__
 
#include<stdlib.h>
#include<stdio.h>
#include<assert.h>
 
typedef char DataType;
 
typedef struct BTreeNode
{
	DataType data;
	struct BTreeNode *left;
	struct BTreeNode *right;
}BTreeNode;
 
void CreatBTree(BTreeNode **cur, DataType *str, DataType invalid, int *index);
void Preorder(BTreeNode *cur);
void Inorder(BTreeNode *cur);
void Postorder(BTreeNode *cur);
void Destroy(BTreeNode **cur);
void CpBTree(BTreeNode *cur, BTreeNode **ret);
int BTreeHight(BTreeNode *cur);
int BTreeNum(BTreeNode *cur);
int BTree(BTreeNode *cur);
int BTreeKnum(BTreeNode *cur, int K);
BTreeNode *LeftNode(BTreeNode *cur, DataType data);
BTreeNode *RightNode(BTreeNode *cur, DataType  data);
BTreeNode* ParentNode(BTreeNode *cur, DataType  data);
#endif

BTree.c

#include"BTree.h"
 
//申请一个节点
BTreeNode *BuyBTreeNode(DataType data)
{
	BTreeNode *NewNode = (BTreeNode *)malloc(sizeof(BTreeNode));
	if(NULL == NewNode)
	{
		assert(0);
	}
	NewNode->data = data;
	NewNode->left = NULL;
	NewNode->right = NULL;
	return NewNode;
}
//构建树
void CreatBTree(BTreeNode **cur, DataType *str, DataType invalid, int *index)
{
	BTreeNode *ret = NULL;
	assert(cur&&str);
	if(str[*index] && invalid != str[*index])
	{
		(*cur) = BuyBTreeNode(str[*index]);
		(*index)++;
		CreatBTree(&(*cur)->left, str, invalid , index);
		if(str[*index] != '\0')
		{
			(*index)++;
			CreatBTree(&(*cur)->right, str, invalid , index);
		}
	}
}
//拷贝树
void CpBTree(BTreeNode *cur, BTreeNode **ret)
{
	assert(ret);
	if(cur)
	{
		(*ret) = BuyBTreeNode(cur->data);
		CpBTree(cur->left, &(*ret)->left);
		CpBTree(cur->right, &(*ret)->right);
	}
}
//前序遍历
void Preorder(BTreeNode *cur)
{
	if(cur)
	{
		printf("%c",cur->data);
		Preorder(cur->left);
		Preorder(cur->right);
	}
}
//中序
void Inorder(BTreeNode *cur)
{
	if(cur)
	{
		Inorder(cur->left);
		printf("%c",cur->data);
		Inorder(cur->right);
	}
}
//后序
void Postorder(BTreeNode *cur)
{
	if(cur)
	{
		Postorder(cur->left);
		Postorder(cur->right);
		printf("%c",cur->data);
	}
}
//销毁
void Destroy(BTreeNode **cur)
{
	BTreeNode *ret = *cur;
	assert(cur);
	if(*cur)
	{
		Destroy(&ret->left);
		Destroy(&ret->right);
		free(ret);
		ret = NULL;
	}
}
//求树的节点个数
int BTreeNum(BTreeNode *cur)
{
	if(cur == NULL)
		return 0;
	return BTreeNum(cur->left) + BTreeNum(cur->right) + 1;
}
//求树的高度
int BTreeHight(BTreeNode *cur)
{
	int lefthight = 0;
	int righthight = 0;
	if(NULL == cur)
		return 0;
	lefthight = BTreeHight(cur->left);
	righthight = BTreeHight(cur->right);
 
	return lefthight > righthight ? lefthight+1 : righthight+1;
}
//叶子节点
int BTree(BTreeNode *cur)
{
	if(NULL == cur)
		return 0;
	if(NULL == cur->left && NULL == cur->right)
		return 1;
	return BTree(cur->left)+BTree(cur->right);
}
//求第k层的节点
int BTreeKnum(BTreeNode *cur, int K)
{
	if(NULL == cur)
		return 0;
	if(K == 1)
		return 1;
	return BTreeKnum(cur->left,K-1) + BTreeKnum(cur->right,K-1);
}
//求一个节点的左孩子
BTreeNode *LeftNode(BTreeNode *cur, DataType  data)
{
	BTreeNode *ret = NULL;
	if(NULL == cur)
		return NULL;
    if(cur->data == data && cur->left != NULL)
	{
		return cur->left;
	}
	ret = LeftNode(cur->left, data);
		//如果左子数找到的话，就不用进右子树找了
	//如果左子数找不到的话，进入右子树找
	if(ret == NULL)
	   ret =  LeftNode(cur->right, data);
	return ret;
}
//求一个节点的右孩子
BTreeNode *RightNode(BTreeNode *cur, DataType  data)
{
	BTreeNode *ret = NULL;
	if(NULL == cur)
		return NULL;
    if(cur->data == data && cur->right != NULL)
	{
		return cur->right;
	}
	ret = RightNode(cur->left, data);
		//如果左子数找到的话，就不用进右子树找了
	//如果左子数找不到的话，进入右子树找
	if(ret == NULL)
	   ret =  RightNode(cur->right, data);
	return ret;
}
//求一个节点的双亲节点
BTreeNode* ParentNode(BTreeNode *cur, DataType  data)
{
	BTreeNode *ret = NULL;
	if(cur->data == data)
		return NULL;
	if(cur->left->data == data|| cur->right->data == data)
		return cur;
	ret = ParentNode(cur->left, data);
	//如果左子数找到的话，就不用进右子树找了
	//如果左子数找不到的话，进入右子树找
	if(ret == NULL)
	   ret =  ParentNode(cur->right, data);
	return ret;
}