Implentation.java

// 1. General Implementation of LinkedList - from geeksforgeeks.com

class LinkedList
{
    Node head;  // head of list
 
    /* Linked list Node*/
    class Node
    {
        int data;
        Node next;
          
        // Constructor to create a new node
        // Next is by default initialized
        // as null
        Node(int d) {data = d;}
    }
    /* method to create a simple linked list with 3 nodes*/
    public static void main(String[] args)
    {
        /* Start with the empty list. */
        LinkedList llist = new LinkedList();
 
        llist.head  = new Node(1);
        Node second = new Node(2);
        Node third  = new Node(3);
 
        /* Three nodes have been allocated  dynamically.
          We have references to these three blocks as first,  
          second and third
 
          llist.head        second              third
             |                |                  |
             |                |                  |
         +----+------+     +----+------+     +----+------+
         | 1  | null |     | 2  | null |     |  3 | null |
         +----+------+     +----+------+     +----+------+ */
 
        llist.head.next = second; // Link first node with the second node
 
        /*  Now next of first Node refers to second.  So they
            both are linked.
 
         llist.head        second              third
            |                |                  |
            |                |                  |
        +----+------+     +----+------+     +----+------+
        | 1  |  o-------->| 2  | null |     |  3 | null |
        +----+------+     +----+------+     +----+------+ */
 
        second.next = third; // Link second node with the third node
 
        /*  Now next of second Node refers to third.  So all three
            nodes are linked.
 
         llist.head        second              third
            |                |                  |
            |                |                  |
        +----+------+     +----+------+     +----+------+
        | 1  |  o-------->| 2  |  o-------->|  3 | null |
        +----+------+     +----+------+     +----+------+ */
    }
}

//2. Traversal of LinkedList

class LinkedList
{
    Node head;  // head of list
 
    /* Linked list Node.  This inner class is made static so that
       main() can access it */
    static class Node {
        int data;
        Node next;
        Node(int d)  { data = d;  next=null; } // Constructor
    }
 
    /* This function prints contents of linked list starting from head */
    public void printList()
    {
        Node node = head;
        while (node != null)
        {
            System.out.print(node.data+" ");
            node = node.next;
        }
    }
 
    /* method to create a simple linked list with 3 nodes*/
    public static void main(String[] args)
    {
        /* Start with the empty list. */
        LinkedList llist = new LinkedList();
 
        llist.head       = new Node(1);
        Node second      = new Node(2);
        Node third       = new Node(3);
 
        llist.head.next = second; // Link first node with the second node
        second.next = third; // Link first node with the second node
 
        llist.printList();
    }
}