RemoveDuplicate.java

class LinkedList {

	static Node head;

	static class Node {

		int data;
		Node next;

		Node(int d)
		{
			data = d;
			next = null;
		}
	}

	
	void remove_duplicates()
	{
		Node ptr1 = null, 
        ptr2 = null, 
        dup = null;
		ptr1 = head;

		while (ptr1 != null && ptr1.next != null) {
			ptr2 = ptr1;

			while (ptr2.next != null) {

				if (ptr1.data == ptr2.next.data) {

					
					ptr2.next = ptr2.next.next;
					System.gc();
				}
				else  {
					ptr2 = ptr2.next;
				}
			}
			ptr1 = ptr1.next;
		}
	}

	void printList(Node node)
	{
		while (node != null) {
			System.out.print(node.data + " ");
			node = node.next;
		}
	}

	public static void main(String[] args){

        LinkedList list = new LinkedList();
		list.head = new Node(12);
		list.head.next = new Node(11);
		list.head.next.next = new Node(12);
		list.head.next.next.next = new Node(21);0
		list.head.next.next.next.next = new Node(41);
		list.head.next.next.next.next.next = new Node(43);
		list.head.next.next.next.next.next.next
			= new Node(21);

		System.out.println(
			"Linked List before removing duplicates : ");
		list.printList(head);

		list.remove_duplicates();
		System.out.println("\n");
		System.out.println(
			"Linked List after removing duplicates : ");
		list.printList(head);
	}
}