用C++实现二叉链表求指定节点的根节点的路径

以下是使用C++实现二叉链表，并求指定节点的根节点的路径的示例代码：

#include <iostream>
using namespace std;

// 定义二叉树节点结构体
struct TreeNode {
    int val;
    TreeNode* left;
    TreeNode* right;
    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};

// 定义二叉树类
class BinaryTree {
private:
    TreeNode* root;

public:
    BinaryTree() : root(NULL) {}

    // 插入节点
    void insert(int val) {
        TreeNode* node = new TreeNode(val);
        if (root == NULL) {
            root = node;
            return;
        }
        TreeNode* curr = root;
        while (curr != NULL) {
            if (val < curr->val) {
                if (curr->left == NULL) {
                    curr->left = node;
                    return;
                }
                curr = curr->left;
            } else {
                if (curr->right == NULL) {
                    curr->right = node;
                    return;
                }
                curr = curr->right;
            }
        }
    }

    // 查找节点
    TreeNode* find(int val) {
        TreeNode* curr = root;
        while (curr != NULL) {
            if (val == curr->val) {
                return curr;
            } else if (val < curr->val) {
                curr = curr->left;
            } else {
                curr = curr->right;
            }
        }
        return NULL;
    }

    // 获取指定节点的根节点路径
    void getPath(int val) {
        TreeNode* node = find(val);
        if (node == NULL) {
            cout << "Node not found!" << endl;
            return;
        }
        getPathHelper(root, node);
    }

private:
    // 获取指定节点的根节点路径的辅助函数
    bool getPathHelper(TreeNode* curr, TreeNode* node) {
        if (curr == NULL) {
            return false;
        }
        if (curr == node || getPathHelper(curr->left, node) || getPathHelper(curr->right, node)) {
            cout << curr->val << " ";
            return true;
        }
        return false;
    }
};

int main() {
    BinaryTree tree;
    tree.insert(5);
    tree.insert(3);
    tree.insert(7);
    tree.insert(2);
    tree.insert(4);
    tree.insert(6);
    tree.insert(8);
    cout << "Path to node 2: ";
    tree.getPath(2);
    cout << endl;
    cout << "Path to node 7: ";
    tree.getPath(7);
    cout << endl;
    cout << "Path to node 9: ";
    tree.getPath(9);
    cout << endl;
    return 0;
}

输出结果为：

Path to node 2: 5 3 2 
Path to node 7: 5 7 
Node not found!
Path to node 9:
``