預期的構造函數，析構函數或類型轉換之前，「*」標記

Question

編譯器說

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

，並指向這一行的.cpp：

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

我猜測它可能是一些有關typedef但不是很確定。問題是什麼？

.h文件中：

#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; 
} 

... 

Answer 1

Node聲明的Tree裏面，所以你需要

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