Implement Stack and Queue using LinkList class and compare the performance between StackArray,QueueArray and StackLinkList and QueueLinkList : class LinkList{    private Node first;                                  // ref to first item on list    public Node getFirst()                               // get value of first       { return first; }    public void setFirst(Node f)                       // set first to new link       { first = f; }    public LinkList()                                  // constructor       { first = null; }                                 // no items on list yet    public boolean isEmpty()                           // true if list is empty       { return (first==null); }    public void insertFirst(int dd) {                  // insert at start of list       Node newLink = new Node(dd);                    // make new link       newLink.next = first;                           // newLink --> old first       first = newLink;                                  // first --> newLink       }    public void insertLast(int dd) {                   // insert at start of list       Node newLink = new Node(dd);                    // make new link       Node current = first;       while( current.next != null) {       current = current.next;       }       current.next= newLink;    }// end insertLast    public int deleteFirst(){      // delete first item (assumes list not empty)       Node temp = first;          // save reference to link       first = first.next;         // delete it: first-->old next       temp.next = null;       return temp.iData;          // return deleted link       } // -------------------------------------------------------------    public ListIterator getIterator()       { // return iterator       return new ListIterator(this); // initialized with       }                               //    this list // -------------------------------------------------------------    public void displayList()      {       Node current = first;       // start at beginning of list       while(current != null) {     // until end of list,          current.displayLink();   // print data          current = current.next; // move to next link          }       System.out.println("");       } // -------------------------------------------------------------    public Node find(int key) {    Node current = first;    while ( current != null) {        if(current.iData == key) {        return current;        }//if        current= current.next;    }// while    return null;    }    public Node delete(int key) {    Node prev= first;    Node current = first;    while ( current != null) {        if(current.iData == key) {          prev.next = current.next;          current.next = null;          return current;        }//if       prev = current;        current = current.next;           }// while    return null;    }    public Node deleteLast() {    Node current = first;    Node prev = first;    Node temp = null;    while(current.next != null ) {        prev = current;        current = current.next;    }// end while    temp= current;    prev.next = null;    return temp;    }// end deleteLast // -------------------------------------------------------------    } // end class LinkList     class LinkList2App    {    public static void main(String[] args)       {       LinkList theList = new LinkList(); // make list         theList.insertFirst(22);      // insert 4 items       theList.insertFirst(44);       theList.insertFirst(66);       theList.insertFirst(88);         theList.displayList();              // display list         Node f = theList.find(88);          // find item       if( f != null)          System.out.println("Found link with key " + f.iData);       else          System.out.println("Can't find link");         Node d = theList.delete(66);        // delete item       if( d != null )          System.out.println("Deleted link with key " + d.iData);       else         System.out.println("Can't delete link");         theList.displayList();              // display list       theList.deleteLast();       theList.displayList();       theList.deleteFirst();       theList.displayList();       theList.insertLast(33);       theList.displayList();        theList.insertLast(80);       theList.displayList();       } // end main()    } // end class LinkList2App