Node.java

import java.util.Scanner;
class Node {
    int data;
    Node next;

    Node(int d){
        data = d;
        next = null;
    }

    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;
    }


    static void display(Node head){
        Node start = head;
        while(start != null){
            System.out.print(start.data+" ");
            start = start.next;
        }
        System.out.println();
    }

    static Node removeDuplicates(Node head){

        if(head == null || head.next == null){
            return head;
        }

        Node start = head;
        while(start.next != null){
            if (start.data == (start.next).data){
                start.next = (start.next).next;
            }else{
                start = start.next;
            }
        }
        return head;
    }

    public static void main(String args[])
    {
        Scanner sc=new Scanner(System.in);
        Node head = null;
        System.out.println("Enter a list size: ");
        int T = sc.nextInt();
        while(T-- > 0){
            System.out.println("Enter a number: ");
            int ele = sc.nextInt();
            head = insert(head, ele);
        }
        display(head);
        head = removeDuplicates(head);
        display(head);
    }
}