Day 25.java

import java.util.*;
class Node{
	int data;
	Node next;
	Node(int d){
        data=d;
        next=null;
    }
	
}
class Solution
{

    public static Node removeDuplicates(Node head) {
        if(head==null)
        {
            return head;
        }
        else if(head.next==null||(head.data==head.next.data&&head.next.next==null))
        {
            head.next=null;
            return head;
        }
        else
        {
            Node ptr;
            for(ptr=head;ptr.next!=null;)
            {
                Node k=ptr.next;
                if(ptr.data==k.data)
                {
                    while(k.data==ptr.data)
                    {
                        k=k.next;
                        if(k==null)
                        {
                            break;
                        }
                    }
                    ptr.next=k;
                    continue;
                }
                else
                {
                    ptr=ptr.next;
                }
            }
            return head;
        }
    }

    public static  Node insert(Node head,int data)
    {
        Node p=new Node(data);			
        if(head==null)
            head=p;
        else if(head.next==null)
            head.next=p;
        else
        {
            Node start=head;
            while(start.next!=null)
                start=start.next;
            start.next=p;

        }
        return head;
    }
    public static void display(Node head)
        {
              Node start=head;
              while(start!=null)
              {
                  System.out.print(start.data+" ");
                  start=start.next;
              }
        }
        public static void main(String args[])
        {
              Scanner sc=new Scanner(System.in);
              Node head=null;
              int T=sc.nextInt();
              while(T-->0){
                  int ele=sc.nextInt();
                  head=insert(head,ele);
              }
              head=removeDuplicates(head);
              display(head);

       }
    }