树一线索二叉树

#include <iostream>
using namespace std;

// 线索二叉树节点结构
typedef struct CludeBiNode {
    int data;
    int ltag, rtag;
    struct CludeBiNode *left, *right;
} CludeBiNode, *CludeBiTree;

// 初始化线索二叉树
void InitCludeBiTree(CludeBiTree &T) {
    T = NULL;
}

// 插入节点
void InsertCludeBiNode(CludeBiTree &T, int val) {
    if (T == NULL) {
        T = new CludeBiNode;
        T->data = val;
        T->ltag = 0;
        T->rtag = 0;
        T->left = NULL;
        T->right = NULL;
    } else if (val < T->data) {
        InsertCludeBiNode(T->left, val);
    } else if (val > T->data) {
        InsertCludeBiNode(T->right, val);
    } else {
        cout << "值已存在，插入失败" << endl;
    }
}

// 中序遍历线索化
void InThread(CludeBiTree &p, CludeBiTree &pre) {
    if (p != NULL) {
        InThread(p->left, pre);  // 递归左子树线索化

        if (p->left == NULL) {
            p->left = pre;
            p->ltag = 1;
        }

        if (pre != NULL && pre->right == NULL) {
            pre->right = p;
            pre->rtag = 1;
        }

        pre = p;  // 保持pre指向p的前驱

        InThread(p->right, pre);  // 递归右子树线索化
    }
}

// 创建中序线索二叉树
void CreateInThread(CludeBiTree T) {
    CludeBiTree pre = NULL;
    if (T != NULL) {
        InThread(T, pre);
        pre->right = NULL;  // 处理最后一个节点
        pre->rtag = 1;
    }
}

// 中序遍历线索二叉树
void InOrderTraverse(CludeBiTree T) {
    CludeBiTree p = T;
    while (p != NULL) {
        while (p->ltag == 0) {
            p = p->left;
        }
        cout << p->data << " ";
        while (p->rtag == 1 && p->right != NULL) {
            p = p->right;
            cout << p->data << " ";
        }
        p = p->right;
    }
}

int main() {
    CludeBiTree T;
    InitCludeBiTree(T);

    // 插入一些节点
    InsertCludeBiNode(T, 60);
    InsertCludeBiNode(T, 55);
    InsertCludeBiNode(T, 45);
    InsertCludeBiNode(T, 65);
    InsertCludeBiNode(T, 80);
    InsertCludeBiNode(T, 89);

    // 创建中序线索二叉树
    CreateInThread(T);

    // 中序遍历线索二叉树
    cout << "中序遍历线索二叉树: ";
    InOrderTraverse(T);
    cout << endl;

    return 0;
}