Condensed List | HackerRank Certification | Remove repeated node from a Singly Linked List

 Given a list of integers, remove any nodes that have values that have previously occurred in the list and return a reference to the head of the list.   

For e.g: 

Linked List

Input : 3 --> 4 --> 3 --> 6

Output: 3 --> 4 --> 6 

public static SinglyLinkedListNode(SinglyLinkedListNode head)

{

    var hSet = new HashSet<int>();

    SinglyLinkedListNode newList = new SinglyLinkedListNode();

    while(head != null)

    {

        hSet.Add(head.data);

        head = head.next;

    }

    foreach(int i in hSet)

    {

        newList.InsertNode(i);

    }

    return (newList.head);

}