1. 程式人生 > 實用技巧 >04-樹7 二叉搜尋樹的操作集 (30分)

04-樹7 二叉搜尋樹的操作集 (30分)

本題要求實現給定二叉搜尋樹的5種常用操作。

函式介面定義:

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結構定義如下:

typedef struct TNode *Position;
typedef Position BinTree;
struct TNode{ ElementType Data; BinTree Left; BinTree Right; };
  • 函式InsertX插入二叉搜尋樹BST並返回結果樹的根結點指標;
  • 函式DeleteX從二叉搜尋樹BST中刪除,並返回結果樹的根結點指標;如果X不在樹中,則列印一行Not Found並返回原樹的根結點指標;
  • 函式Find在二叉搜尋樹BST中找到X,返回該結點的指標;如果找不到則返回空指標;
  • 函式FindMin返回二叉搜尋樹BST中最小元結點的指標;
  • 函式FindMax返回二叉搜尋樹BST中最大元結點的指標。

裁判測試程式樣例:

#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 ); /* 先序遍歷,由裁判實現,細節不表 */ void InorderTraversal( BinTree BT ); /* 中序遍歷,由裁判實現,細節不表 */ 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; } /* 你的程式碼將被嵌在這裡 */

輸入樣例:

10
5 8 6 2 4 1 0 10 9 7
5
6 3 10 0 5
5
5 7 0 10 3

輸出樣例:

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

提交測試程式碼:

BinTree Insert(BinTree BST, ElementType X) {
    if (!BST) {
        BST = (BinTree)malloc(sizeof(struct TNode));
        BST->Data = X;
        BST->Left = NULL;
        BST->Right = NULL;
    }
    else if (BST->Data > X) {
        BST->Left = Insert(BST->Left, X);
    }
    else if (BST->Data < X) {
        BST->Right = Insert(BST->Right, X);
    }
    return BST;
}

BinTree Delete(BinTree BST, ElementType X) {
    if (!BST) {
        printf("Not Found\n");
    }
    else 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 != NULL && BST->Right == NULL) {
        BinTree tmp = BST;
        BST = BST->Left;
        free(tmp);
    }
    else if (BST->Left == NULL && BST->Right != NULL) {
        BinTree tmp = BST;
        BST = BST->Right;
        free(tmp);
    }
    else if (BST->Left == NULL && BST->Right == NULL) {
        free(BST);
        BST = NULL;
    }
    else {
        Position tmp = FindMin(BST->Right);
        BST->Data = tmp->Data;
        BST->Right = Delete(BST->Right, BST->Data);
    }
    return BST;
}

Position Find(BinTree BST, ElementType X) {
    if (!BST) {
        return NULL;
    }
    else if (BST->Data > X) {
        return Find(BST->Left, X);
    }
    else if (BST->Data < X) {
        return Find(BST->Right, X);
    }
    else {
        return BST;
    }
}

Position FindMin(BinTree BST)
{
    if (!BST)
    {
        return NULL;
    }
    else if (BST->Left != NULL) {
        return FindMin(BST->Left);
    }
    else {
        return BST;
    }
}

Position FindMax(BinTree BST)
{
    if (!BST) {
        return NULL;
    }
    else if (BST->Right != NULL) {
        return FindMax(BST->Right);
    }
    else {
        return BST;
    }
}

提測結果:

完整自測程式碼:

#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); /* 先序遍歷,由裁判實現,細節不表 */
void InorderTraversal(BinTree BT);  /* 中序遍歷,由裁判實現,細節不表 */

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;
}

void PreorderTraversal(BinTree T){
    if (!T) {
        return;
    }
    printf(" %d", T->Data);
    if(T->Left){
        PreorderTraversal(T->Left);
    }
    if (T->Right){
        PreorderTraversal(T->Right);
    }
}

void InorderTraversal(BinTree T)
{
    if (!T) {
        return;
    }
    if (T->Left) {
        InorderTraversal(T->Left);
    }
    printf(" %d", T->Data);
    if (T->Right) {
        InorderTraversal(T->Right);
    }
}

BinTree Insert(BinTree BST, ElementType X) {
    if (!BST) {
        BST = (BinTree)malloc(sizeof(struct TNode));
        BST->Data = X;
        BST->Left = NULL;
        BST->Right = NULL;
    }
    else if (BST->Data > X) {
        BST->Left = Insert(BST->Left, X);
    }
    else if (BST->Data < X) {
        BST->Right = Insert(BST->Right, X);
    }
    return BST;
}

BinTree Delete(BinTree BST, ElementType X) {
    if (!BST) {
        printf("Not Found\n");
    }
    else 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 != NULL && BST->Right == NULL) {
        BinTree tmp = BST;
        BST = BST->Left;
        free(tmp);
    }
    else if (BST->Left == NULL && BST->Right != NULL) {
        BinTree tmp = BST;
        BST = BST->Right;
        free(tmp);
    }
    else if (BST->Left == NULL && BST->Right == NULL) {
        free(BST);
        BST = NULL;
    }
    else {
        Position tmp = FindMin(BST->Right);
        BST->Data = tmp->Data;
        BST->Right = Delete(BST->Right, BST->Data);
    }
    return BST;
}

Position Find(BinTree BST, ElementType X) {
    if (!BST) {
        return NULL;
    }
    else if (BST->Data > X) {
        return Find(BST->Left, X);
    }
    else if (BST->Data < X) {
        return Find(BST->Right, X);
    }
    else {
        return BST;
    }
}

Position FindMin(BinTree BST)
{
    if (!BST)
    {
        return NULL;
    }
    else if (BST->Left != NULL) {
        return FindMin(BST->Left);
    }
    else {
        return BST;
    }
}

Position FindMax(BinTree BST)
{
    if (!BST) {
        return NULL;
    }
    else if (BST->Right != NULL) {
        return FindMax(BST->Right);
    }
    else {
        return BST;
    }
}