6-12 二叉搜索树的操作集 (30分)
本题要求实现给定二叉搜索树的5种常用操作。
函数接口定义:
BinTree Insert( BinTree BST, ElementType X );
BinTree Delete( BinTree BST, ElementType X );
Position Find( BinTree BST, ElementType X );
Position FindMin( BinTree BST );
Position FindMax( BinTree BST );
其中BinTree结构定义如下:
typedef struct TNode *Position;
typedef Position BinTree;
struct TNode{
ElementType Data;
BinTree Left;
BinTree Right;
};
函数Insert将X插入二叉搜索树BST并返回结果树的根结点指针;
函数Delete将X从二叉搜索树BST中删除,并返回结果树的根结点指针;如果X不在树中,则打印一行Not Found并返回原树的根结点指针;
函数Find在二叉搜索树BST中找到X,返回该结点的指针;如果找不到则返回空指针;
函数FindMin返回二叉搜索树BST中最小元结点的指针;
函数FindMax返回二叉搜索树BST中最大元结点的指针。
裁判测试程序样例:
#include <stdio.h>
#include <stdlib.h>
typedef int ElementType;
typedef struct TNode *Position;
typedef Position BinTree;
struct TNode{
ElementType Data;
BinTree Left;
BinTree Right;
};
void PreorderTraversal( BinTree BT ); /* 先序遍历,由裁判实现,细节不表 */
void InorderTraversal( BinTree BT ); /* 中序遍历,由裁判实现,细节不表 */
BinTree Insert( BinTree BST, ElementType X );
BinTree Delete( BinTree BST, ElementType X );
Position Find( BinTree BST, ElementType X );
Position FindMin( BinTree BST );
Position FindMax( BinTree BST );
int main()
{
BinTree BST, MinP, MaxP, Tmp;
ElementType X;
int N, i;
BST = NULL;
scanf("%d", &N);
for ( i=0; i<N; i++ ) {
scanf("%d", &X);
BST = Insert(BST, X);
}
printf("Preorder:"); PreorderTraversal(BST); printf("\n");
MinP = FindMin(BST);
MaxP = FindMax(BST);
scanf("%d", &N);
for( i=0; i<N; i++ ) {
scanf("%d", &X);
Tmp = Find(BST, X);
if (Tmp == NULL) printf("%d is not found\n", X);
else {
printf("%d is found\n", Tmp->Data);
if (Tmp==MinP) printf("%d is the smallest key\n", Tmp->Data);
if (Tmp==MaxP) printf("%d is the largest key\n", Tmp->Data);
}
}
scanf("%d", &N);
for( i=0; i<N; i++ ) {
scanf("%d", &X);
BST = Delete(BST, X);
}
printf("Inorder:"); InorderTraversal(BST); printf("\n");
return 0;
}
/* 你的代码将被嵌在这里 */
输入样例:
10
5 8 6 2 4 1 0 10 9 7
5
6 3 10 0 5
5
5 7 0 10 3
输出样例:
Preorder: 5 2 1 0 4 8 6 7 10 9
6 is found
3 is not found
10 is found
10 is the largest key
0 is found
0 is the smallest key
5 is found
Not Found
Inorder: 1 2 4 6 8 9
BinTree Insert(BinTree BST, ElementType X)
{
if (!BST)
{
BST = (BinTree)malloc(sizeof(struct TNode));
if (!BST)
return NULL; //内存分配失败
BST->Data = X;
BST->Left = BST->Right = NULL;
}
else
{
if (BST->Data > X)
BST->Left = Insert(BST->Left, X);
else
BST->Right = Insert(BST->Right, X);
}
return BST;
}
BinTree Delete(BinTree BST, ElementType X)
{
if (BST)
{
if (BST->Data > X)
BST->Left = Delete(BST->Left, X);
else if (BST->Data < X)
BST->Right = Delete(BST->Right, X);
else
{
if (BST->Left && BST->Right)
{
BinTree p = FindMin(BST->Right);
BST->Data = p->Data;
BST->Right = Delete(BST->Right, BST->Data);
}
else
{
BinTree p = BST;
if (BST->Right)
BST = BST->Right;
else if (BST->Left)
BST = BST->Left;
else
BST = NULL;
free(p);
}
return BST;
}
}
else
printf("Not Found\n");
return BST;
}
Position Find(BinTree BST, ElementType X)
{
if (!BST || BST->Data == X)
return BST;
else if (BST->Data > X)
return Find(BST->Left, X);
else
return Find(BST->Right, X);
}
Position FindMin(BinTree BST)
{
if (!BST)
return NULL;
Position Min = BST;
Position Left = FindMin(BST->Left);
Position Right = FindMin(BST->Right);
if (Left && Left->Data < Min->Data)
Min = Left;
if (Right && Right->Data < Min->Data)
Min = Right;
return Min;
}
Position FindMax(BinTree BST)
{
if (!BST)
return NULL;
Position Max = BST;
Position Left = FindMax(BST->Left);
Position Right = FindMax(BST->Right);
if (Left && Left->Data > Max->Data)
Max = Left;
if (Right && Right->Data > Max->Data)
Max = Right;
return Max;
}