C++:When creating a new objects inside a function and returning it as result, must I use the new operator to create the object?

Question

I have two dummy questions which have confused me for a while. I did do some searching online and read through much c++ tutorials, however I cannot find concrete answers.

Answer 1

What you did probably mean is:

Node* func()
{ 
    Node n(10); 
    return &n;
}

But that would lead to undefined behavior, as the Node n would be on the stack and not under your control.

Node* func()
{ 
    Node* n = new Node(10); 
    return n;
}

That would work, but you would need to free the Node* in your destructor.

If you can use c++11 features I'd probably go with an std::unique_ptr:

class Node
{
   int data;
   std::unique_ptr next;
}
std::unique_ptr func()
{ 
    std::unique_ptr n(new Node(10)); 
    return n;
}

That way your Node would be freed by the destructor of the std::unique_ptr<>.