Eclipse 抱怨递归函数调用

Question

一个简单的二叉搜索树类声明：

#include <vector>
#include <stdio.h>

// Provides various structures utilized by search algorithms.

// Represents an generalized node with integer value and a set of children.
class Node {
protected:
    std::vector<Node*> children;
    int value;
public:
    //Creates a new instance of a Node with a default value=-1.
    Node(){value = -1;}
    //Creates a new instance of a Node with a specified value.
    explicit Node(int value){this->value = value;}
    virtual ~Node(){delete children;}

    //Adds new Node with specified value to the list of child nodes. Multiple
    //children with the same value are allowed.
    //Returns added node.
    virtual Node* Insert(int value);
    //Removes first occurrence of a Node with specified value among children.
    virtual void Remove(int value);
};

// Represents a binary search tree node with at most two children.
class BTNode: public Node {
public:
    //Creates a new instance of a BTNode with a default value=-1.
    BTNode():Node(){}
    //Creates a new instance of a BTNode with a specified value.
    explicit BTNode(int value):Node(value){}

    //Adds new BTNode with specified value to the list of child nodes in an
    //ordered manner, that is right child value is >= value of this node and
    //left child value < value of this node.
    virtual BTNode* Insert(int value);
    //Removes first occurrence of a Node with specified value from the tree.
    virtual void Remove(int value);
    //Returns a node with specified value.
    virtual BTNode* Search(int value);
};

而 eclipse 抱怨它的定义：

BTNode* BTNode::Search(int value){
    if (this->value == value) return *this;

    //Determines whether value is in left(0) or right(1) child.
    int child = this->value > value ? 0 : 1;
    if (children[child] != NULL)
        return children[child]->Search(value);

    return NULL;
}

调用children[child]->Search(value) 的确切位置出现消息“方法搜索无法解析”。 构建运行良好（没有任何编译错误）。这有什么问题？

P.S.：还没有尝试运行代码。正在努力。

Answer 1

Search 是BTNode 接口的一部分，但它不是Nodes 接口的一部分，children 是Node* 的vector，因此在a 上调用Search 是无效的Node *。如果Node 有一个Search 方法是有意义的，那么将它添加到Node 将解决这个问题。如果不是，那么您需要重新考虑您的设计，这可能超出了这个问题的范围。

还有其他一些问题。你有：

virtual ~Node(){delete children;}

但children 不是pointer，而是std::vector<Node*>。您需要遍历 vector 并调用 delete 每个元素。在Search 你有这个：

if (this->value == value) return *this;

但是 Search 返回一个 BTNode* 所以它应该是：

if (this->value == value)  return this ;