/*
 * Main.java
 *
 * Created on February 6, 2008, 1:48 PM
 *
 *
 * MORE UP TO DATE VERSION IS IN LIST_DLL_purge with classname LIST_purge
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package list_dll_purge;

/**
 *
 * @author suchenek
 */
//Copyright Dr. Marek A. Suchenek, 2005, 2006, 2007, 2008 ,2009, 2010, 2011 - 2025

public class LIST_DLL_purge
{
	public static void main (String[] args)
	{
		LIST_DLL L = new LIST_DLL();
		Object x;
		x = new int[] {1};
		L.Insert(L.First(), x);
		x = new int[] {2};
		L.Insert(L.First(), x);
		x = new int[] {3};
		L.Insert(L.First(), x);
		x = new int[] {4};
		L.Insert(L.First(), x);
		x = new int[] {3};
		L.Insert(L.First(), x);
		L.Insert(L.End(), x);
		L.Insert(L.First(), x);
		L.Insert(L.End(), x);
		
		for (POSITION_DLL p = L.First(); !p.isEqual(L.End()); p = L.Next(p)) 
				System.out.println(((int[])L.Select(p))[0]);
		System.out.println("Purge it!");				

		LIST_DLL_purge.Purge(L);

		for (POSITION_DLL p = L.First(); !p.isEqual(L.End()); p = L.Next(p)) 
				System.out.println(((int[])L.Select(p))[0]);
		System.out.println("Same, in the reverse order");
		for (POSITION_DLL p = L.End(); !p.isEqual(L.First()); p = L.Previous(p)) 
				System.out.println(((int[])L.Select(L.Previous(p)))[0]);
		
	}
	
	public static void Purge(LIST_DLL L) 
	{

		for (POSITION_DLL p = L.First(); !p.isEqual(L.End()); p = L.Next(p)) 
		{
			Object x = L.Select(p);
			POSITION_DLL q = L.Next(p);
			while (!q.isEqual(L.End())) 
			{
				Object y = L.Select(q);
				if (LIST_DLL_purge.isEqual(x, y)) L.Delete(q);
				else q = L.Next(q);
			}
		}
	}

	public static boolean isEqual(Object x, Object y) 
	{
		return (((int[])x)[0] == ((int[])y)[0]);
	}
	
}