Need help combining 2 lists into 1 new list. Almost there

[nomdaweb]

I am trying to combine list1 and list2 into newlist but am having a few errors. After these 2 lists combine, their values will be zero

LinkedList catList(LinkedList &list1, LinkedList &list2)
{
	ListNode *nodePtr;
	LinkedList newList;
	newList = catList(list1, list2);

	newList = createList();

	*nodePtr -> list1.head;

	while(*nodePtr->data !NULL)
	{
		*nodePtr -> list1.data;
	}

	*nodePtr ->list2.head;

	newList = list1;

	list1.size = 0;
	list2.size = 0;

	list1 =NULL;
	list2 = NULL;

	return newList;
}

Any help would be appreciated, thank you.

[computerkazi]

try creating list 3 based on the total size of list 1 and 2. then insert list 1 followed by list 2 into list 3