1. LAB#4#5
Linked
List

2. Linked List Linked List :A B C
Head
Tail
A linked list is a series of connected nodes.
Each node contains at least:
A piece of data (any type)
Pointer to the next node in the list
Head: pointer to the first node.
The last node points to NULL.
node A
data
pointer

3. Linked List Singly Linked List : We use two classes: Node and List
Declare IntSLLNode class for the nodes
class IntSLLNode {
public:
IntSLLNode() { next = 0; }
IntSLLNode(int i, IntSLLNode *ptr = 0)
{ info = i;
next = ptr; }
int info;
IntSLLNode *next; };

4. Linked List Singly Linked List : Declare IntSLList which contains :
class IntSLList {
public:
IntSLList() {head = tail =0; }
void AddToHead(int);
void AddToTail(int);
void DeleteFromHead();
void DeleteFromTail();
void DeleteNode(int);
bool isInList(int) const;
void DisplayList();
private:
IntSLLNode *head, *tail; };

5. Linked List Singly Linked List : void IntSLList::AddToHead(int el) {
Declare IntSLList Class member function:
1- void AddToHead(int);
void IntSLList::AddToHead(int el) {
head = new IntSLLNode(el,head);
if (tail == 0)
tail = head; }

6. Linked List Singly Linked List : void IntSLList::AddToTail(int el) {
Declare IntLList Class member function:
2- void AddToTail(int);
void IntSLList::AddToTail(int el) {
if (tail != 0) // if list not empty;
{ tail->next = new IntSLLNode(el);
tail = tail->next; }
else
head = tail = new IntSLLNode(el); }

7. Linked List Singly Linked List : void IntSLList::DeleteFromHead(){
Declare IntLList Class member function:
3- void DeleteFromHead();
void IntSLList::DeleteFromHead(){
if(head !=0) {
IntSLLNode *tmp =head;
if (head == tail) //if only one node in the list
head = tail = 0;
else head = head ->next;
delete tmp;} }

8. Linked List Singly Linked List : 4- void DeleteFromTail();
void IntSLList::DeleteFromTail()
{if(head != 0)
{if (head == tail) //if only one node in the list
{delete head;
head=tail=0;}
else { IntSLLNode *tmp; //find the predecessor of tail
for(tmp=head; tmp->next != tail; tmp = tmp->next);
delete tail;
tail=tmp;
tail->next=0;}} }

9. Linked List Singly Linked List :
Declare IntLList Class member function:
5- int DeleteNode(int el);

10. Linked List

11. Linked List Singly Linked List :
Declare IntLList Class member function:
6- bool isInList(int) const;
bool IntSLList:: isInList(int el) const {
IntSLLNode *tmp;
for (tmp=head; tmp != 0 && !(tmp->info == el);
tmp = tmp->next);
return tmp !=0; }

12. Linked List Singly Linked List : void IntSLList::DisplayList()
Declare IntSLList Class member function:
7- void DisplayList();
void IntSLList::DisplayList()
{IntSLLNode *current;
current = head;
cout << "head = " << head << "\n";
while(current != 0)
{cout << current->info << " " << current << "\n";
current=current->next;}
cout << "tail = " << tail << "\n";
cout << " " << "\n";}

13. Linked List Singly Linked List : Using List : void main()
{IntSLList myllist;
myllist.AddToHead(50);
myllist.AddToHead(90);
myllist.AddToHead(60);
myllist.AddToHead(68);
myllist.DisplayList();
myllist.DeleteFromHead();
myllist.DeleteNode(60);
if (myllist.isInList(60)== 0)
cout<<"60 isn't in the list" << endl;
Else cout<<"60 is in the list" << endl;
myllist.DisplayList();}

14. Linked List Doubly Linked List : Declare IntDLLNode which contains :
class IntDLLNode{
public:
IntDLLNode() {next=prev=0;}
IntDLLNode(int el,IntDLLNode *n=0,IntDLLNode *p=0){
info = el; next=n; prev =p; }
Int info;
IntDLLNode *next, *prev; };

15. Linked List Doubly Linked List : Declare IntDLList which contains :
class IntDLList{
public:
IntDLList(){
Head=tail=0;}
void addToDLLTail(int el);
void deleteFromDLLTail();
void DisplayFromHead();
protected:
IntDLLNode *head ,*tail; };

16. Linked List Doubly Linked List : void IntDLList:: addToDLLTail(int el)
Declare IntDLList Class member function:
1- void addToDLLTail(int el);
void IntDLList:: addToDLLTail(int el)
{if (tail!=0){
tail=new IntDLLNode(el,0,tail);
tail->prev->next=tail;}
else
head=tail=new IntDLLNode(el); }

17. Linked List Doubly Linked List : void IntDLList:: deleteFromDLLTail()
Declare IntDLList Class member function:
2- void deleteFromDLLTail()
void IntDLList:: deleteFromDLLTail()
{if(tail !=0){
if(head==tail) { //if only one node in the list
delete head;
head = tail =0;}
else {
tail = tail->prev;
delete tail->next;
tail->next = 0;}}}

18. Linked List Doubly Linked List : void IntDLList::DisplayFromHead() {
Declare IntDLList Class member function:
2- void IntDLList::DisplayFromHead();
void IntDLList::DisplayFromHead() {
IntDLLNode *current;
for( current = head ; current != 0 ; current = current->next )
cout<<current->info<<endl;
cout<<" "<<endl; }