在' * '标记之前预期的构造函数、析构函数或类型转换

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error: expected constructor, destructor, or type conversion before ‘*’ token"

并指向.cpp中的这一行:

Node * Tree::buildTree(Node *myNode, int h) {

我猜它可能是关于typedef的东西，但不是很确定。问题是什么呢?

. h文件:

#ifndef TREE_H
#define TREE_H
class Tree {
    public:
    Tree();
    Tree(Tree const & other);
    ~Tree();
    Tree const & operator=(Tree const & other);
    private:
    class Node {
        public:
        Node() {
            data = 0;
        };
        Node(Node const & other) {
            _copy(other);
        };
        ~Node() {};
        Node const & operator=(Node const & other) {
            if (this != &other) 
                _copy(other);
            return *this;
        };
        Node *left;
        Node *right;
        int data;
        private:
        void _copy(Node const & other) {
            data = other.data;
            left = other.left;
            right = other.right;
        };
    };
    Node *root;
    Node * buildTree(Node *myNode, int h);
};

. cpp文件:

...
Node * Tree::buildTree(Node *myNode, int h) {
    if (h == 0)
        return NULL;
    myNode = new Node();
    myNode->left = buildTree(myNode->left, h - 1);
    myNode->right = buildTree(myNode->right, h - 1);
    return myNode;
}
...