How to add to tail of a DoublyLinkedCircularList

[ritchson101]

I had the following question in my exam and got 2 out of a possible 6 marks

Here is the question:

Implement a function for the DoublyLinkedCircularList class with the signature addToTail(T element) which will append the element passed in as a parameter to the back of the list

Here is my solution

template<class T>
void DoublyLinkedCircularList<T> :: addToTail(T element)
{
	DoublyLinkedNode<T>* head;
	DoublyLinkedNode<T>* temp;
	temp->element = element;
	if(tail == null)
	{
		tail = temp;
		temp -> next = temp; //Wrong
	}
	
	head = tail->next;
	tail->next = temp; //Correct - mark
	temp -> next = head; //Correct - mark
}

I basically only got marks for the last two lines of code

Can anyone help me figure out the correct way to complete this question?