Chapter 3, Problem 6R

Explanation of Solution

Method to find the second-to-last node in singly linked list to indicates the last node as null next reference:

//Define the secondToLast() method

private Node<E> secondToLast( )

{

  //Check whether the size is less than "2"

  if (size < 2)

  //Throw an exception

throw new IllegalStateException("List contains two or more entries");

  //Create a node to hold the head value

Node<E> ptr = head;

/*Loop executes until the "ptr" is not equal to "null". */

  while (ptr−>next−>next != null)

/*Second to last node is determined and assigned to "ptr"...