dk15

// Java program to remove duplicates
// from a sorted linked list
class LinkedList {
	// head of list
	Node head;
	// Linked list Node
	class Node {
		int data;
		Node next;
		Node(int d)
		{
			data = d;
			next = null;
		}
	}

	// Function to remove duplicates from the given linked
	// list
	void removeDuplicates()
	{
		// Two references to head temp will iterate to the
		// whole Linked List prev will point towards the
		// first occurrence of every element
		Node temp = head, prev = head;

		// Traverse list till the last node
		while (temp != null) {

			// Compare values of both pointers
			if (temp.data != prev.data) {
				// if the value of prev is not equal to the
				// value of temp that means there are no
				// more occurrences of the prev data. So we
				// can set the next of prev to the temp
				// node.
				prev.next = temp;
				prev = temp;
			}
			//Set the temp to the next node
			temp = temp.next;
		}
		// This is the edge case if there are more than one
		// occurrences of the last element
		if (prev != temp)
			prev.next = null;
	}

	/* Utility functions */

	/* Inserts a new Node at front of the list. */
	public void push(int new_data)
	{
		/* 1 & 2: Allocate the Node &
				Put in the data*/
		Node new_node = new Node(new_data);
		/* 3. Make next of new Node as head */
		new_node.next = head;
		/* 4. Move the head to point to new Node */
		head = new_node;
	}

	/* Function to print linked list */
	void printList()
	{
		Node temp = head;
		while (temp != null) {
			System.out.print(temp.data + " ");
			temp = temp.next;
		}
		System.out.println();
	}

	/* Driver program to test above functions */
	public static void main(String args[])
	{
		LinkedList llist = new LinkedList();
		llist.push(20);
		llist.push(13);
		llist.push(13);
		llist.push(11);
		llist.push(11);
		llist.push(11);

		System.out.print("List before ");
		System.out.println("removal of duplicates");
		llist.printList();

		llist.removeDuplicates();

		System.out.println(
			"List after removal of elements");
		llist.printList();
	}
}

// This code is contributed by Sania Kumari Gupta