Question

class Node { public Object data = null; public Node next = null; Node head = new Node(); // first Node head.next = new Node(); // second Node head.next.next = new Node(); // third node head.next.next next = new Node(); // fourth node head=head.next.next= new Node();

what one line of code would i need to remove the first node?

Answer 1

//one line code to remove first node would be

head=head.next;

=======================

//I am giving complete program to understand it better

//Let's have Node.java file in which class Node is defined and in Main.java we are going to decare list of type Node to represent linked list

Node.java

class Node

{

  public Object data=null;

  public Node next=null;

}

=====================

//Main.java

class Main {

public static void main(String[] args) {

Node head=new Node(); //first node

//just adding data to show how it works

head.data=1;

head.next=new Node(); //second node

head.next.data=2;

head.next.next=new Node(); //third node

head.next.next.data=3;

head.next.next.next =new Node(); //fourth node

head.next.next.next.data=4;

//print data before removing first node

System.out.println("Linked list elements are : "+head.data+" "+head.next.data+" "+head.next.next.data+" "+head.next.next.next.data);

//one line code to remove first node would be

head=head.next;

System.out.println("Linked list after removing first node is : "+head.data+" "+head.next.data+" "+head.next.next.data);

}

}

/*Output

 java -classpath .:/run_dir/junit-4.12.jar Main

Linked list elements are : 1 2 3 4

Linked list after removing first node is : 2 3 4

*/

As first node with data 1 is removed after statement

head=head.next;

we get linked list as 2 3 4