1. IntNode Class class IntNode { public: int info; class IntNode *next; IntNode(int el, IntNode *ptr = 0) { info = el; next = ptr; } }; diagrammatic representation: * Material presented here is taken mostly from Drozdek’s book, “Data Structures and Algorithms in C++” infonext

2. IntNode Class IntNode *p = new IntNode(10); p->info == 10; p->next == 0 ; after the statement is executed p->next = new IntNode(8); 10 p p 8

3. IntNode Class p->next->next = new IntNode(50); See if you can draw the resulting diagram. Exercise. Draw a diagram to illustrate the configuration of linked nodes that is created by the following statements. IntNode *p0 = new IntNode(3); IntNode *p1 = p0->next = new IntNode(5); IntNode *p2 = p1->next = new IntNode(9); Exercise. Write the C++ statements that are needed to created the configurations (to be drawn on the blackboard)

4. Exercise diagram

5. Linked List (non-OO) How to create a list (1, 3, 5, 6, 7, 9)? Draw a series of diagrams first

6. Linked List ADT (.h) class IntSList { public: IntSLList() { head = tail = 0; } ~IntSLList(); int isEmpty() { return head == 0; } void addToHead(int); void addToTail(int); int deleteFromHead(); // delete the head and // return its info; int deleteFromTail(); // delete the tail and // return its info; void deleteNode(int); bool isInList(int) const; void printAll() const; private: IntNode *head, *tail; };

7. Linked List ADT (.cpp) #include using std::cout; #include "intSLLst.h" IntSLList::~IntSLList() { for (IntNode *p; !isEmpty(); ) { p = head->next; delete head; head = p; }

8. Linked List ADT (.cpp) void IntSLList::addToHead(int el) { head = new IntNode(el,head); if (tail == 0) tail = head; } void IntSLList::addToTail(int el) { if (tail != 0) { // if list not empty; tail->next = new IntNode(el); tail = tail->next; } else head = tail = new IntNode(el); }

9. Linked List ADT (.cpp) int IntSLList::deleteFromHead() { int el = head->info; IntNode *tmp = head; if (head == tail) // if only one node on the //list; head = tail = 0; else head = head->next; delete tmp; return el; }

10. Linked List ADT (.cpp) int IntSLList::deleteFromTail() { int el = tail->info; if (head == tail) { // if only one node on the list; delete head; head = tail = 0; } else { // if more than one node in the //list, IntNode *tmp; // find the predecessor of tail; for (tmp = head; tmp->next != tail; tmp = tmp->next); delete tail; tail = tmp; // the predecessor of tail // becomes tail; tail->next = 0; } return el; }

11. Linked List ADT (.cpp) void IntSLList::deleteNode(int el) { if (head != 0) // if non-empty list; if (head == tail && el == head->info) { // if only one node on the list; delete head; head = tail = 0; } else if (el == head->info) { // if more than one node on the list IntNode *tmp = head; head = head->next; delete tmp; // and old head is deleted; } else { // if more than one node in the list IntNode *pred, *tmp;

12. Linked List ADT (.cpp) // and a non-head node is deleted; for (pred = head, tmp = head->next; tmp != 0 && !(tmp->info == el); pred = pred->next, tmp = tmp->next); if (tmp != 0) { pred->next = tmp->next; if (tmp == tail) tail = pred; delete tmp; }

13. Linked List ADT (.cpp) bool IntSLList::isInList(int el) const { IntNode *tmp; for (tmp = head; tmp !=0 && !(tmp->info == el); tmp = tmp->next); return tmp != 0; } void IntSLList::printAll() const { for (IntNode *tmp = head; tmp != 0; tmp = tmp->next) cout info << " "; cout << "\n"; }

14. Doubly Linked List class IntNode { public: int info; class IntNode *next, *Prev; IntNode(int el, IntNode *ptrn = 0, IntNode *ptrp = 0) { info = el; next = ptrn; prev = ptrp; } }; diagrammatic representation: infonextprev

15. Stack First-in, Last-out (FILO) Can be implemented with array or linked list Has many applications

16. Queue First-in, First-out (FIFO) Can be implemented with array or linked list Has many applications