Modify the $$LinkedStackOfStrings$.$java$$ program given in the textbook $($program $4\mathrm{.}3\mathrm{.}2)$ by adding a method $$find$()$ that takes a string as an argument. It should return true if the string argument is in the linked stack and false otherwise. $[$MO$6\mathrm{.}1]$

The main method should also be modified so that all the strings $($other than the search string$)$ inputted by the user are stored on the stack before calling the find$()$ method.

Sample runs would be as follows.

$>$java LinkedStackOfStrings hello

this

is a

test run

for the

hello program

hello exists in the linked stackpubTic class LinkedStackOfStrings

$\{$

private Node first;

private class Node

$\{$

private String item;

private Node next;

$\}$

public boolean isEmpty$()$

$\{$ return $($first $==$ nu$11)$; $\}$

public void push$($String item$)$

$\{//$ Insert a new node at the beginning of the list.

Node oldFirst $=$ first;

first $=$ new Node $()$;

first.item $=$ item;

first.next $=$ oldFirst;

$\}$

public String pop$()$

$\{//$ Remove the first node from the list and return item.

String item $=$ first. item;

first $=$ first.next;

return item;

$\}.$

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

$\{$

LinkedStackOfStrings stack $=$ new LinkedStackOfStrings$()$;

$//$ See Program $4\mathrm{.}3\mathrm{.}1$ for the test client.

$\}$

$\}$