第4章 树 - 二叉搜索树数据结构实现

#ifndef _Tree_H

struct TreeNode;
typedef struct TreeNode *Position;
typedef struct TreeNode *SearchTree;

SearchTree MakeEmpty( SearchTree T);
Position Find( int X, SearchTree T);
Position FindMin( SearchTree T);
Position FindMax( SearchTree T);
SearchTree Insert( int X, SearchTree T);
SearchTree Delete( int X, SearchTree T);
int Retrieve( Position P);
int Depth( SearchTree T);
#endif

#include <iostream>
#include "SearchTree.h"
using namespace std;

struct TreeNode
{
int Element;
SearchTree Left;
SearchTree Right;
};

SearchTree MakeEmpty( SearchTree T)
{
if(T != NULL)
{
MakeEmpty(T->Left);
MakeEmpty(T->Right);
free(T);
}
return T;
}

Position Find( int X, SearchTree T)
{
if(T == NULL)
return NULL;
else if(X < T->Element)
return Find(X, T->Left);
else if(X > T->Element)
return Find(X, T->Right);
else
return T;
}

Position FindMin(SearchTree T)
{
if(T == NULL)
return NULL;
else if(T->Left == NULL)
return T;
else
return FindMin(T->Left);
}

Position FindMax(SearchTree T)
{
if(T != NULL)
while (T->Right != NULL)
T = T->Right;
return T;
}

SearchTree Insert( int X, SearchTree T)
{
if(T == NULL)
{
T = (TreeNode*)malloc(sizeof(TreeNode));
T->Element = X;
T->Left = T->Right = NULL;
}
else if(X < T->Element)
T->Left = Insert(X, T->Left);
else if(X > T->Element)
T->Right = Insert(X, T->Right);

return T;
}

SearchTree Delete( int X, SearchTree T)
{
Position TmpCell;
if(T == NULL)
return NULL;
else if(X < T->Element)
T->Left = Delete(X, T->Left);
else if(X > T->Element)
T->Right = Delete(X, T->Right);
else if(T->Left && T->Right)
{
TmpCell = T;
T = FindMin(T->Right);
T->Right = Delete(T->Element, T->Right);
free(TmpCell);
}
else
{
TmpCell = T;
if(T->Left != NULL)
T = T->Left;
if(T->Right != NULL)
T = T->Right;
free(TmpCell);
}

return T;
}
<pre name="code" class="cpp">int Depth( SearchTree T)
{
int DepthLeft, DepthRight;
if(T == NULL)
return 0;
else
{
DepthLeft = Depth(T->Left);
DepthRight = Depth(T->Right);
if(DepthLeft >= DepthRight)
return DepthLeft + 1;
else
return DepthRight + 1;
}
}