ArrayList Methods Practice Test

In this library catalog, what is printed after calling remove and then size?

import java.util.ArrayList;

public class LibraryDemo {

    public static void main(String[] args) {

        ArrayList<String> books = new ArrayList<String>(); // create catalog

        books.add("Dune");

        books.add("1984");

        books.add("Hamlet");

        books.remove(1); // remove "1984"

        System.out.println(books.size()); // number of books left

    }

}

In this inventory system, what is the output after using set and then get?

import java.util.ArrayList;

public class InventoryDemo {

    public static void main(String[] args) {

        ArrayList<Integer> qty = new ArrayList<Integer>(); // quantities per item

        qty.add(5);

        qty.add(2);

        qty.add(9);

        qty.set(1, 7); // update second item's quantity

        System.out.println(qty.get(1)); // print updated quantity

    }

}