1. JAVA & Linked List Implementation
Group VI Presented by Regulapati Venkata Ramana Rao

2. Objective Purpose Types of linked list Organization
Different operations
Bio-Oh of each operation
Case study

3. Introduction Is the linear data structure represented by nodes
Is an alternative to the contiguous array implementation
It Consists of collection of connected , dynamically allocated Nodes
Each node will have at least two elements
Element itself
The link to the next node in the list
Link to next node
Element 11 12

4. Introduction Class ListNode { Linked List Node Representation
Object element;
ListNode nextNode; }

5. Introduction Why Linked List ?
Inserting or deleting of an item into/from list is easy, where as it requires extensive data movement if we use arrays
Insertion Into Sorted Array
Insert 4 into above array
Increase the array size
Locate the position of 4. Big-oh is O(N)
Move the elements by one position. Big-oh is O(N)
So Big-Oh is O(N2) 1 2 3 5 6 7

6. Introduction Array After Inserting Linked List Implementation
Inserting Element 4
Create new node with element 4
ListNode tmp = new ListNode();
tmp.element = 4;
Search the position of element Big-Oh(N) 1 2 3 4 5 6 7
header 1 2 5 6
tmp 4

7. Introduction Insertion… Note: So Linked list is efficient in this case
Point the new node link to the node after the new node
temp.next = current.next;
Point the previous node link to new node
current.next = tmp;
Big-Oh is O(N)
Note: So Linked list is efficient in this case
current 1 2 5 6
tmp 4

8. Types Linked Lists are 3 types Single Linked List
Consists of data element and reference to the next Node in the Linked list
First node is accessed by reference (Header Node)
Last node is set to NULL
Head 11 12 13

9. Types Double Linked List
Consists of nodes with two link members one points to the previous and other to the next node
Maximizes the needs of list traversals
Compared to the Singled list inserting and deleting nodes is a bit slower as both the links has to be updated
It requires the extra storage space for the second link
Head 11 11 11

10. Types Circular Linked list
Similar to the doubly linked list, but the last node link points to the first node instead of null
Useful in algorithms where there is no particular first or last item
Advantage is we can make head to point any node without destroying the list
Operations are similar to single linked list except identifying the last node in the list. To find the last node compare the last node to head node (i.e you have found the last node if its link points to the same node that the head points)

11. Types
Circularly Linked List Representation
first 11 12 13

12. Header & Trailer Nodes
Header Node: A placeholder node at the beginning of list, used to simplify list processing.It doesn’t hold any data but satisfies that the every node has a previous node.
Trailer Node: A placeholder node at the end of list, used to simplify list processing

13. Single LinkedList Operations
Insertion of node
Consider 3 cases of insertion
Node is first node in the linked list
Node is an inner node
Node is last node
Deleting specific node
Printing/Traversing Liked List
Find specific node
Find Length of Linked List

14. Implementation
All the above mentioned operations are implemented on a sorted singly linked list in the following example
The implementation has these classes
List.java … This is the interface
LinkedList.java … Implementation for the methods declared in interface
Node.java … This is actual Node in Linked list and also has Accessor / Mutator methods
TestLinkedList.java … Test client program

15. List.java Interface

16. Node.java

17. Node.java

18. LinkedList.java
//This class Implements the List interface

19. LinkedList.java

20. LinkedList.java

21. LinkedList.java

22. LinkedList.java

23. LinkedList.java

24. LinkedList.java

25. InvalidElementException.java

26. ClientLinkedList.java

27. ClientLinkedList.java

28. ClientLinkedList.java