How does the new keyword make a difference?

Question

class sortedList
{
    class Node
    {
        public:
            int value;
            Node* next;

            Node()
            {
                this->value = 0;
                this->next = NULL;
            }
            Node(int value)
            {
                this->value = value;
                this->next = NULL;
            } 
    }* head = NULL, * tail = NULL;

    public:
        void addNode(int value)
        {
            Node* n = Node(value);
            //More code...
        }
};

Why does adding new before Node(value) make the code correct? I think the code above should stay wrong because pointer doesn't equal a node.

Answer 1

This is not valid code:

Node* n = Node(value);

The reason new makes it work is that new returns a pointer.

You can either declare your Node using dynamic storage:

Node* n = new Node(value);

or automatic storage:

Node n(value);