Step $1$: Inspect the NumberListNode.java file

Inspect the class declaration for a doubly$-$linked list node in NumberListNode.java. The NumberListNode class has three fields:

data: A double for the node's numerical data value

next: A reference to the next node

previous. A reference to the previous node

Each field is protected. So code outside of the class must use the provided getter and setter methods to get or set a field.

NumberListNode.java is read$-$only since no changes are required.

Step $2$: Inspect NumberList.java and SortedNumberList.java

NumberList.java contains the NumberList class definition. NumberList is a base class for a double$-$linked list of NumberListNodes. The

list's head and tail fields are protected, and a printo utility method exists to print the list s contents from head to tail. The file is read$-$only

since no changes are required.

SortedNumberList.java contains the SortedNumberList class definition. SortedNumberList extends NumberList and adds insert$()$ and

remove$()$ methods.

Step $3$: Implement insert$()$

Implement SortedNumberLists insert$0$ method to create a new node with the number argument as the node s data then insert the

node into the proper sorted position in the linked list. Ex Suppose a SortedNumberlists sument sist $15\mathrm{.}2347\mathrm{.}2586$

then insert $)$ is called. A new node with data value $33\mathrm{.}5$ screated and inserted between $23$ and $43\mathrm{.}25$ thus preserving the list's

sorted order and yielding: $2335\mathrm{.}547\mathrm{.}2586$

Step $4$: Run code and verify output

An array of doubles named numbersTolnsert is defined near the start of main$().$ Each is inserted into a SortedNumberList, and the list is

printed after each insertion. Try changing the array's content, and verify that each output is a sorted list.

Step $5$: Implement remove$()$

Implement SortedNumberList's remove$($ method. The method takes an argument for the number to remove from the list. If the number

does not exist in the list, the list is not changed and false is returned. Otherwise, the first instance of the number is removed from the

list and true is returned.

Once remove$($ is implemented, change the value of the includeRemovals variable, defined at the start of main $0,$ from false to true. Run

the code and make sure that the list is correct after each removal.

Try different tests in main$()$ as needed then submit code for grading. Unit tests are used to grade submitted code, so output from

main$($ does not affect grading.

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Files

$$

Main,java

Main.java

NumberList,java

boolean includeRemovals $=$ false;

$1,$ Numbers $to$ insent duning finst Loop:

double$[]$ numberstoInsent $=f7\mathrm{.}75,15\mathrm{.}25,-4\mathrm{.}25,63,5,18\mathrm{.}25,-3,5$

NumberListNode.java

Main.java

$1$ import java.util.Scanner;

import java.io$.$PrintWriter;

public class Main $\{$

public static void main$($String$[]$ args$)\{$

boolean includeRemovals $=$ false;

$//$ Numbers to insert during first loop:

double$[]$ numbersToInsert $=\{$

$77\mathrm{.}75,15\mathrm{.}25,-4\mathrm{.}25,63\mathrm{.}5,18\mathrm{.}25,-3\mathrm{.}5$

$\}$;

$//$ Insert each value and show the sorted list's contents after ea

SortedNumberList list $=$ new SortedNumberList$()$;

for $($double number : numbersToInsert$)\{$

for $($double number : numbersToInsert$)\{$

System.out.print$("$List after inserting $"+$ number $+"$: $")$;

list.insert$($number$)$;

list.print$($System$.$out$)$;

$\}$

If $($includeRemovals$)\{$

System.out.println$()$;

double$[]$ numbersToRemove $=\{$

$77\mathrm{.}75,//$ List's last element

$-4\mathrm{.}25,//$ List's first element

$18\mathrm{.}25,//$ Neither first nor last element

$//$ Remaining elements:

$15\mathrm{.}25,63\mathrm{.}5,-3\mathrm{.}5$

$//$ Remaining elements:

$15\mathrm{.}25,63\mathrm{.}5,-3\mathrm{.}5$

$\}$;

$//$ Remove numbers

for $($double toRemove : numbersToRemove$)\{$

System.out.print$("$List after removing $"+$ toRemove $+"$: $")$;

list.remove$($toRemove$)$;

list.print$($System$.$out$)$;

$\}$

$\}$

$\}$

$\}$