Remove duplicates from an unsorted linked list

Question

import java.util.*;
/*
 *  Remove duplicates from an unsorted linked list
 */
public class LinkedListNode {  
    public int data;  
    public LinkedListNode next;          


        

Answer 1

I think you can just use one iterator current to finish this problem 

public void compress(){
    ListNode current = front;
    HashSet set = new HashSet();
    set.add(current.data);
    while(current.next != null){
       if(set.contains(current.next.data)){
          current.next = current.next.next;         }
         else{
            set.add(current.next.data);
            current = current.next;
         }
      }

}