Question

Please make sure the code works perfectly and is accurate. This is high-stake assignment. I will rate highly, thank you very much for saving my life.

Question:

Create a Java program that extends the LinkedList<E> class of java.util.* to ExtLinkedList<E> that would have these methods:

public class ExtLinkedList<E> extends LinkedList<E> {

public ExtLinkedList<E>subList() {

.... (stuff goes here)

}

}

which returns the values stored at index 0,3,6,9, … of the list. If given an empty list it should simply return the empty list. For example, subList() method for a non-empty list containing values {e0,e1,e2,e3, e4,e5,e6,e7} should return a list containing (e0, e3,e6}. The original list should not be modified. Your code should work for any size including the empty list and any parameter E. Also, the original LinkedList should remain intact and not have any of its contents removed. Estimate the run-time complexity of the method given the size of the original list is n.   

No constructor is needed for the class ExtLinkedList<E> class.

Answer 1

Program:

import java.util.*;

//class ExtLinkedList
public class ExtLinkedList<E> extends LinkedList<E>
{
   //method to create the sublist
   public ExtLinkedList<E>subList()
   {
       ExtLinkedList<E> sublist = new ExtLinkedList<E>();
      
       ListIterator<E> itr = listIterator();

for(int i = 0; itr.hasNext(); i++)
{
E element = itr.next();
  
if(i % 3 == 0)
{
sublist.add(element);
}
}
return sublist;
   }
}

//class Driver
class Driver
{
   //main method
   public static void main (String[] args)
   {
       //Create the linked list
       ExtLinkedList<String> list = new ExtLinkedList <String>();
  
       //add the elements
       list.addLast("e0");
   list.addLast("e1");
   list.addLast("e2");
   list.addLast("e3");
   list.addLast("e4");
   list.addLast("e5");
   list.addLast("e6");
   list.addLast("e7");
  
   Iterator itr = list.iterator();

       //display the original list
       System.out.print("The original LinkedList: ");
   for(int i = 0; itr.hasNext(); i++)
{
System.out.print(itr.next() + " ");
}

   System.out.println();
ExtLinkedList<String> sublist = list.subList();
  
itr = sublist.iterator();
  
//display the sublist
System.out.print("The sublist: ");
for(int i = 0; itr.hasNext(); i++)
{
System.out.print(itr.next() + " ");
}
   }
}

Output:

The run-time complexity of the method given the size of the original list is n: O(n), since it needs to traverse and access each node of the original list .

N.B. Whether you face problem or you need help then share me in the comment section, I'll be happy to help you.