// Written by:	Darren Gates & Ray Klefstad
// Date:	January 2000
// School:	U.C. Irvine

import java.awt.*;
import java.applet.*;

public class LinkedListsExample
    extends Applet
{
    private TextArea display;
    
    public void init()
    {
	display = new TextArea(8, 35);
        add(display);
        String result = "";
        
        LinkedList myList = new LinkedList();
        myList.insert("list.");
        myList.insert("my");
        myList.insert("is");
        myList.insert("This");
        result += myList.toString() + "\n";
        
        int found1 = myList.find("hello");
        int found2 = myList.find("This");
        int found3 = myList.find("list.");
        
        result += "Now testing find method (-1 if not found)...\n\n";
        result += "'hello' is found at position: " + found1 + "\n";
        result += "'list.' is found at position: " + found3 + "\n";       
        result += "'This' is found at position: " + found2 + "";
        
        display.setText(result);
    }
}

class LinkedList
{
    public static class Node
    {
        private Object info;
        private Node next;
        
        public Node(Object newInfo, Node newNext)
        {
            info = newInfo;
            next = newNext;
        }
    }
    
    private Node head;
    
    public LinkedList()
    {
        head = null;
    }
    
    public void insert(Object info)
    {
        head = new Node(info, head);
    }
    
    public int find(Object info)
    {
        int i = 0;
        
        for (Node cur = head; cur != null; cur = cur.next, i++)
        {
            if (info.equals(cur.info))
                return i;
        }
        return -1;  // not found
    }
    
    public String toString()
    {
        String result = "";
        
        for (Node cur = head; cur != null; cur = cur.next)
            result += cur.info + " ";

        return result;
    }
}