为结构分配内存

Question

Example

struct Node
{
    int data;
    Node *left;
    Node *right;
};

void allocate(const int data, Node *&n)
{
    ;
    // How do we allocate memory here?
    //n = new Node(data, nullptr, nullptr);
}

void remove(Node *&n) { delete n; }

int main()
{
    Node *n;
    allocate(1, n);
    remove(n);
}

---

What is the proper way to allocate memory to n in the function allocate . I am not sure how to properly initialize a struct.

Answer 1

You may do this in this way:

n = new Node {data, nullptr, nullptr};

Complete Code:

struct Node
{
    int data;
    Node *left;
    Node *right;
};

void allocate(const int data, Node *&n)
{
    ;
    // How do we allocate memory here?
    n = new Node{data, nullptr, nullptr};
}

void remove(Node *&n) { delete n; }

int main()
{
    Node *n;
    allocate(1, n);
    remove(n);
}

Suggestions :

1) In C++, struct can also have constructors. So, instead of using a separate function for this, you must define constructor.

2) Never use naked new . You must consider smart pointers like unique_ptr and shared_ptr