//Class Node
public class Node {
    public int data;
    public Node next;

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

}

//Class LinkedList
public class LinkedList {

    Node head;


    public void push(int new_data){
        if(head==null){
            head=new Node(new_data);
            return;
        }

        Node newNode=new Node(new_data);
        newNode.next=head;
        head=newNode;
    }

    public int getCount(){
        if(head==null) return 0;

        Node temp=head;

        int count=0;

        while(temp!=null){

            //System.out.println(temp.data);
            count++;
            temp=temp.next;

        }

        return count;
    }

    //Bonus task
    public Node getMiddleNode() throws Exception{

        if(head==null) throw new Exception("The list is empty.");

        if(head.next==null) return head;


        Node temp1=head;
        Node temp2=head;

        while(temp2!=null){
            if(temp2.next==null) return temp1;

            temp1=temp1.next;
            temp2=temp2.next.next;

        }

        return temp1;

    }

    public static void main(String[] args){

        LinkedList llist=new LinkedList();
        llist.push(1);
        llist.push(3);
        llist.push(1);
        llist.push(2);
        llist.push(1);
        llist.push(10);
        llist.push(12);


        System.out.println("Count of nodes is: "+ llist.getCount());

        try {
            Node node=llist.getMiddleNode();
            System.out.println("Middle node is: " +node.data);
        } catch (Exception ex) {
            System.out.println(ex.getMessage());
        }

    }


}