可以使用一个指针将节点插入到BST中吗？

#include <iostream>

struct TreeNode {
    int val;
    TreeNode* left;
    TreeNode* right;
    TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
};

void insertNode(TreeNode*& root, int value) {
    if (root == nullptr) {
        root = new TreeNode(value);
        return;
    }

    if (value < root->val) {
        insertNode(root->left, value);
    } else {
        insertNode(root->right, value);
    }
}

int main() {
    TreeNode* root = nullptr;

    // 插入节点
    insertNode(root, 5);
    insertNode(root, 3);
    insertNode(root, 7);
    insertNode(root, 2);
    insertNode(root, 4);

    // 打印BST中的节点值
    std::cout << "BST中的节点值：" << std::endl;
    std::cout << root->val << " ";
    std::cout << root->left->val << " ";
    std::cout << root->right->val << " ";
    std::cout << root->left->left->val << " ";
    std::cout << root->left->right->val << " ";

    return 0;
}