Question

how to implement a memory safe copy constructor? what do i check for?

Answer 1

btw, this is in C++

Answer 2

List::List(const List& aList)
: size(aList.size) {
if (aList.head == NULL)
head = NULL; // original list is empty

else { // copy first node
head = new ListNode;
head->item = aList.head->item;

// copy rest of list
ListNode *newPtr = head; // new list pointer
// newPtr points to last node in new list
// origPtr points to nodes in original list
for (ListNode *origPtr = aList.head->next;
origPtr != NULL;
origPtr = origPtr->next) {
newPtr->next = new ListNode;
newPtr = newPtr->next;
newPtr->item = origPtr->item;
} // end for

newPtr->next = NULL;
} // end if
} // end copy constructor