Use the LinkedList class to simulate a queue, and use the add method to simulate the enqueue, and the remove method to simulate the dequeue method for a Queue. Remember to use FIFO. Create 3 queues, one called Animal Shelter, another called Cats, and another called Dogs. Use the following menu-driven application: 0. Add New Microchips 1. Donate a Cat 2. Donate a Dog 3. Adopt a Cat 4. Adopt a Dog 5. Adopt Oldest Pet 6. Exit

import java.util.*;

public class Q {

  public static LinkedList<String> dogs = new LinkedList<String> ();

  public static LinkedList<String> cats = new LinkedList<String> ();

  public static LinkedList<String> animals = new LinkedList<String> ();

  public static void enqueueCats(){

      System.out.println("Enter name");

      Scanner sc=new Scanner(System.in);

      String name = sc.next();

      cats.addLast(name);

      animals.addLast(name);

  }

  public static void enqueueDogs(){

      System.out.println("Enter name");

      Scanner sc=new Scanner(System.in);

      String name = sc.next();

      dogs.addLast(name);

      animals.addLast(name);

  }

  public static void removeFromQueue(char q,String name){

      LinkedList<String> L = new LinkedList<String> ();

      switch (q) {

          case 'c':

              L = cats;

              break;

          case 'd':

              L = dogs;

              break;

          case 'a':

              L = animals;

      }

      LinkedList<String> tmp = new LinkedList<String> ();

      while (!L.isEmpty()){

          if(!L.getFirst().equals(name)){

              tmp.add(L.getFirst());

          }

          L.removeFirst();

      }

      while (!tmp.isEmpty()){

          L.add(tmp.removeLast());

      }

  }

  public static void dequeueCats(){

      System.out.println("Enter name");

      Scanner sc=new Scanner(System.in);

      String name = sc.next();

      removeFromQueue('c',name);

      removeFromQueue('a',name);

  }

  public static void dequeueDogs(){

      System.out.println("Enter name");

      Scanner sc=new Scanner(System.in);

      String name = sc.next();

      removeFromQueue('d',name);

      removeFromQueue('a',name);

  }

  public static void dequeueAnimals(){

      System.out.println("Enter name");

      Scanner sc=new Scanner(System.in);

      String name = sc.next();

      removeFromQueue('a',name);

      removeFromQueue('d',name);

      removeFromQueue('c',name);

  }

  public static void display(){

      System.out.println("animals:");

      for (String s : animals)

           System.out.print(s);

       System.out.println();

       System.out.println("cats:");

      for (String s : cats)

           System.out.print(s);

       System.out.println();

       System.out.println("dogs:");

      for (String s : dogs)

           System.out.print(s);

       System.out.println();

  }

  public static void display_choices(){

      String [] choices = {"Donate a Cat","Donate a Dog","Adopt a Cat","Adopt a Dog","Adopt Oldest Pet","Exit"};

      for (int i=0;i<choices.length ;i++ ) {

          System.out.println((i+1)+"."+choices[i]);

      }

  }

  public static void main(String[] args) {

      Scanner sc=new Scanner(System.in);

      while(true){

          display_choices();

          int choice=sc.nextInt();

          switch (choice) {

              case 1 :

                  enqueueCats();

                  display();

                  break;

              case 2 :

                  enqueueDogs();

                  display();

                  break;

              case 3 :

                  dequeueCats();

                  display();

                  break;

              case 4 :

                  dequeueDogs();

                  display();

                  break;

              case 5:

                  dequeueAnimals();

                  display();

              case 6 :

                  System.exit(0);

          }

      }

  }

}