Data Structures -- Linked List Find the nth last element in linked list.

[iGuest 3]

import java.Util.LinkedList;public class LinkedListDelete {  public static void main(String args[]) {   LinkedList<String> ll = new LinkedList<String>();   ll.Add("B");   ll.Add("C");   ll.Add("D");   ll.Add("E");   ll.Add("F");   ll.AddLast("Z");   ll.AddFirst("A");   ll.Add(1, "A2");   System.Out.Println("Original contents of ll: " + ll);   ll.Remove("F");   ll.Remove(2);   System.Out.Println("Contents of ll after deletion: " + ll);   ll.RemoveFirst();   ll.RemoveLast();   System.Out.Println("ll after deleting first and last: " + ll);   String val = ll.Get(2);   ll.Set(2, val + " Changed");   System.Out.Println("ll after change: " + ll);  }}

[iGuest 3]

hai incase of doubly circle linked list we can traverse from startptr and endptr so if two traversals are done same time we can get the element in o(n/2) complexity
algorithm is

  startptr=head->llink;endptr= head->rlink;while(startptr!=endptr){if(head->llink!=NULL&&head->rlink!=NULL)  {	startptr=startptr->next;	endptr= endptr->llink;	 while(endptr->llink!=endptr->rlink)	 {	   if(endptr->info==key)		{		  printf("key is found",endptr->info);			}		 else			{			   endptr=endptr->llink;			   if(endptr->llink->llink!=NULL)			  {				printf("element is found %d"endptr->next->info);				 }			    startptr=startptr->rlink;	endptr= endptr->llink;	 while(startptr->llink!=startptr->rlink)	 {	   if(startptr->info==key)		{		  printf("key is found",startptr->info);			}		 else			{			   startptr=startptr->rlink;			   if(startptr->rlink->rlink!=NULL)			  {				printf("element is found %d",statptr->rlink->info);				 }

hai buddy i think if you execute this code you can find 5 th element in o(n/2) complexity
but the linked list must be circularlinkedlist thanks

bye
Edited August 20, 2012 by velma (see edit history)