Java Program to Delete a Node From the Ending of the Circular Linked List

// Java Program to Delete a Node From the Ending of the
// Circular Linked List

public class Main {
    // Represents the node of list.
    public class Node {
        int val;
        Node next;
        public Node(int val) { this.val = val; }
    }

    // Initialising head and tail pointers
    public Node head = null;
    public Node tail = null;

    // add new node to the end
    public void addNode(int val)
    {
        // Creating new node
        Node node = new Node(val);

        // head and tail will point to new node
        // if list is empty
        if (head == null) {
            head = node;
            tail = node;
            node.next = head;
        }
        // otherwise tail point to new node and
        else {
            tail.next = node;
            tail = node;
            tail.next = head;
        }
    }

    // Deletes node from the end of the list
    public void delete()
    {
        // returns if list is empty
        if (head == null) {
            return;
        }
        // otherwise head will point to next element in the
        // list and tail will point to new head
        else {
            // if list contains more than one element
            // then loop will iterate
            // till second last element
            // is pointing to tail
            if (head != tail) {
                Node current = head;
                while (current.next != tail) {
                    current = current.next;
                }
                // Second last element is the new tail
                tail = current;
                tail.next = head;
            }

            // if the list contains only one element
            // then both head and tail will point to null
            else {
                head = tail = null;
            }
        }
    }

    // displaying the nodes
    public void printNode()
    {
        Node current = head;
        if (head == null) {
            System.out.println("List is empty");
        }
        else {
            do {
                System.out.print(" " + current.val);
                current = current.next;
            } while (current != head);
            System.out.println();
        }
    }

    public static void main(String[] args)
    {
        Main list = new Main();

        // Adds data to the list
        list.addNode(5);
        list.addNode(3);
        list.addNode(4);

        // Printing original list
        System.out.println("Original List: ");
        list.printNode();

        // deleting node from ending
        // till the list is empty and
        // displaying the Updated list
        while (list.head != null) {
          
            list.delete();
          
            // Printing updated list
            System.out.println("Updated List: ");
            list.printNode();
        }
    }
}