//============ TO DO ============ // COMPLETE THE methods in the SList class and the needed testing condition // in the main method (the driver) // DOCUMENT and COMMENT the code appopriately. /////////////////////////////////////////////////////

/** ========== COMPLETE THE FOLLOWING CLASS========== * An INCOMPLETE template for a generic type singly linked list class - * You should complete this class and create a driver to test it */ public class SList2 { //note: T is a a placeholder for a data type

//======= Start of nested class ========= /** * The Node class to encapsulate the data and reference of a data structure * node - the class is rewritten as an nested class * @author Ken Nguyen * @version 2 - Node class nested for exclusive used by the list class */ class Node{ private T data; private Node next; public Node(T data){ //initialize the attributes this.data = data; this.next = null; } } //====== end of nested class ========

//attributes of the list class private Node head; private int size; /** * Default constructor - when invoke will return a list object with * a null head and size of 0 */ public SList2(){ this.head = null; this.size = 0; } /** * add the given data as a node to the end of the list * @param data - data to be added to the end of the list * @return - the reference to the newly added Node object containing * the data in the list */ public Node addLast(T data){ //empty list, create it as the first node if(this.head == null){ return this.addFirst(data); } //processing non-empty list Node newNode = new Node(data);

//TO BE COMPLETED return newNode; } /** * add the given data as the first node of the list * @param data - data to be added as the first node to the list * @return - the reference to the newly added Node object containing the * data in the list */ public Node addFirst(T data){ Node newNode = new Node(data); // TO BE COMPLETED return this.head; } /** * remove the first node of the list */ public void removeFirst(){ //TO BE COMPLETED } /** * remove the last node of the list */ public void removeLast(){ //TO BE COMPLETED } /** * @return a string representing the list */ public String toString(){ Node temp = this.head; String output = ""; while(temp != null){ output += temp.data + " " ; temp = temp.next; } return output; } /** * * @return the number of nodes in the list */ public int getSize() { return this.size; } //============================================================= //==== A DRIVER to test the SList class - // REMOVE THE DRIVER BEFORE RELEASE ==== //============================================================= public static void main(String args[]){

//== Add code to test all functionalities of the SList class== //create a list of intergers SList2 myList = new SList2 (); myList.addFirst(5); //add avalue // myList.addLast(10); myList.addFirst(1); myList.addFirst (9); myList.addFirst(3); // myList.addLast(2); System.out.println("List size: " + myList.getSize()); System.out.println(myList); myList.removeFirst(); System.out.println("List size: " + myList.getSize()); System.out.println(myList); myList.removeLast(); System.out.println("List size: " + myList.getSize()); System.out.println(myList); //TO BE COMPLETED //1. add code to invoke removeFirst and removeLast from an empty list } //==== END of the DRIVER ============= }