データ構造の学習経験共有(二叉樹に関する内容)

struct BinaryTreeNode                 //          
{
    int                    m_nValue;    //         
    BinaryTreeNode*        m_pLeft;     //    
    BinaryTreeNode*        m_pRight;    //    
};

BinaryTreeNode* CreateBinaryTreeNode(int value);         //       
void ConnectTreeNodes(BinaryTreeNode* pParent, BinaryTreeNode* pLeft, BinaryTreeNode* pRight);  //       
 void PrintTreeNode(BinaryTreeNode* pNode);       //       
 void PrintTree(BinaryTreeNode* pRoot);          //     
void DestroyTree(BinaryTreeNode* pRoot);         //     

// 《  Offer——            》  
//       ：   

#include "StdAfx.h"
#include "BinaryTree.h"

BinaryTreeNode* CreateBinaryTreeNode(int value)             //       
{
    BinaryTreeNode* pNode = new BinaryTreeNode();
    pNode->m_nValue = value;
    pNode->m_pLeft = NULL;
    pNode->m_pRight = NULL;

    return pNode;
}

void ConnectTreeNodes(BinaryTreeNode* pParent, BinaryTreeNode* pLeft, BinaryTreeNode* pRight)  //       
{
    if(pParent != NULL)
    {
        pParent->m_pLeft = pLeft;
        pParent->m_pRight = pRight;
    }
}

void PrintTreeNode(BinaryTreeNode* pNode)                             //      
{
    if(pNode != NULL)
    {
        printf("value of this node is: %d
", pNode->m_nValue);

        if(pNode->m_pLeft != NULL)
            printf("value of its left child is: %d.
", pNode->m_pLeft->m_nValue);
        else
            printf("left child is null.
");

        if(pNode->m_pRight != NULL)
            printf("value of its right child is: %d.
", pNode->m_pRight->m_nValue);
        else
            printf("right child is null.
");
    }
    else
    {
        printf("this node is null.
");
    }

    printf("
");
}

void PrintTree(BinaryTreeNode* pRoot)      //       
{
    PrintTreeNode(pRoot);

    if(pRoot != NULL)
    {
        if(pRoot->m_pLeft != NULL)
            PrintTree(pRoot->m_pLeft);

        if(pRoot->m_pRight != NULL)
            PrintTree(pRoot->m_pRight);
    }
}

void DestroyTree(BinaryTreeNode* pRoot)
{
    if(pRoot != NULL)
    {
        BinaryTreeNode* pLeft = pRoot->m_pLeft;
        BinaryTreeNode* pRight = pRoot->m_pRight;     //                         ，      ，     

        delete pRoot;
        pRoot = NULL;

        DestroyTree(pLeft);
        DestroyTree(pRight);
    }
}