CSE 2341 Object Oriented Programming with C++ Note Set #18

1. CSE 2341Object Oriented Programming with C++Note Set #18

2. Overview • Dynamic Data structures with linked lists

3. Linked List • Series of connected nodes • Can grow/shrink at runtime • dynamic allocation of nodes allows for this Data Head Null

4. Linked List Node Data struct ListNode { double data; ListNode* next; }; ListNode is a self referentialdata structure.

5. Basic Linked List Operations • Basic Operations of LL • appending a node • traversing the list • inserting a node • deleting a node • destroying the list

6. Class NumberList class NumberList { private: struct ListNode { double value; ListNode* next; }; ListNode* head; private: NumberList() {head = NULL;} ~NumberList(); void appendNode(double); void insertNode(double); void deleteNode(double); void displayList(); };

7. AppendNode void NumberList::appendNode(double num) { ListNode* newNode, *nodePtr; newNode = new ListNode; newNode -> value = num; newNode -> next = NULL; if(!head) //If there aren’t any nodes in list head = newNode; else { nodePtr = head; while(nodePtr->next) nodePtr = nodePtr->next; nodePtr -> next = newNode; } }

8. Append newNode Null 5 Head 3 4 Null NodePtr

9. Append newNode Null 5 Head 3 4 Null NodePtr

10. Append newNode Null 5 Head 3 4 NodePtr

11. Display List void NumberList::DisplayList() { ListNode* nodePtr; nodePtr = head; while(nodePtr) { cout << nodePtr->value << endl; nodePtr = nodePtr->next; } }

12. Display NodePtr Head Null 3 4 5 3

13. Display NodePtr Head Null 3 4 5 3 4

14. Display NodePtr Head Null 3 4 5 3 4 5

15. Display NodePtr Head Null 3 4 5 3 4 5

16. Insert A Node void NumberList::insertNode(double num) { ListNode *newNode, *nodePtr, *previousNode; newNode = new ListNode; newNode -> value = num; if(!head) { head = newNode; newNode->next = NULL; } else { nodePtr = head; previousNode = NULL;

17. Insert A Node //Continued from previous slide while(nodePtr != NULL && nodePtr->value < num) { previousNode = nodePtr; nodePtr = nodePtr->next; } if(previousNode == NULL) //if insert as first { head = newNode; newNode -> next = nodePtr; } else { previousNode -> next = newNode; newNode -> next = nodePtr; } } }

18. Insert newNode 4.5 PreviousNode NodePtr Null Head Null 3 4 5

19. NodePtr Insert newNode 4.5 PreviousNode Head Null 3 4 5

20. NodePtr Insert newNode 4.5 PreviousNode Head Null 3 4 5

21. NodePtr Insert newNode 4.5 PreviousNode Head Null 3 4 5

22. NodePtr Insert newNode 4.5 PreviousNode Head Null 3 4 5

23. NodePtr Insert newNode 4.5 PreviousNode Head Null 3 4 5

24. NodePtr Insert newNode 4.5 PreviousNode Head Null 3 4 5

25. Deleting A Node void NumberList::deleteNode(double num) { ListNode *nodePtr, *previousNode; if(!head) return; if(head->value == num) { nodePtr = head->next; delete head; head = nodePtr; } else { nodePtr = head; while(nodePtr != NULL && nodePtr->value != num) { previousNode = nodePtr; nodePtr = nodePtr->next; } if(nodePtr) { previousNode->next = nodePtr -> next; delete nodePtr; } } }

26. Delete num 4 PreviousNode NodePtr Null Head Null 3 4 5

27. Delete num 4 PreviousNode NodePtr Head Null 3 4 5

28. Delete num 4 PreviousNode NodePtr Head Null 3 4 5

29. Delete num 4 PreviousNode NodePtr Head Null 3 4 5

30. Fini ?