CSharp Solution

using System;

class Node
{
    public int data;
    public Node next;

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

class Solution
{
    public static Node removeDuplicates(Node head)
    {
        var curr = head;
        while (curr != null && curr.next != null)
        {
            while (curr.next != null && curr.data == curr.next.data)
            {
                curr.next = curr.next.next;
            }
            curr = curr.next;
        }
        return head;
    }

    public static Node insert(Node head, int data)
    {
        var 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)
        {
            Console.Write(start.data + " ");
            start = start.next;
        }
    }

    static void Main(String[] args)
    {

        Node head = null;
        int T = int.Parse(Console.ReadLine());
        while (T-- > 0)
        {
            int data = int.Parse(Console.ReadLine());
            head = insert(head, data);
        }
        head = removeDuplicates(head);
        display(head);
    }
}