GROUNDWORK
Chapter 7 - Arrays and Lists

Name: ________________________________     Date: ______________

Fill in every blank. Where a term is asked for, write the word the course
uses. Where code is asked for, write exact Java. Where output is asked
for, write what the program prints, one line per line.


VOCABULARY
----------

 1. The line int[] scores = {88, 92, 79}; makes one __________________:
    many values of one type, held in one variable, in order, with a length
    fixed when it is made.

 2. Each item in an array or a list has a position called its
    __________________. Java counts these starting from zero.

 3. The property that lets an array's items be changed after it is
    created, unlike the letters of a String, is called
    __________________.

 4. Taking a section of an array into a new array, as
    Arrays.copyOfRange(letters, 1, 4) does, is called
    __________________. The original array is left untouched.


READING CODE
------------

 5. What does this print?

        String[] names = {"Ada", "Grace", "Alan", "Katherine"};
        IO.println(names[1]);
        IO.println(names[names.length - 1]);

    ____________________________________

 6. What does this print?

        String[] letters = {"a", "b", "c", "d", "e", "f"};
        IO.println(Arrays.toString(Arrays.copyOfRange(letters, 2, 5)));
        IO.println(Arrays.toString(Arrays.copyOfRange(letters, 0, 2)));

    ____________________________________

 7. What does this print?

        ArrayList<Integer> scores = new ArrayList<>(List.of(88, 92, 79));
        ArrayList<Integer> ordered = new ArrayList<>(scores);
        Collections.sort(ordered);
        IO.println(ordered);
        IO.println(scores);

    ____________________________________

 8. What does this print?

        ArrayList<Integer> a = new ArrayList<>(List.of(1, 2, 3));
        ArrayList<Integer> b = a;
        b.add(4);
        IO.println(a);

    ____________________________________

 9. What does this print?

        String[] names = {"Ada", "Grace", "Alan"};
        for (int i = 0; i < names.length; i++) {
            IO.println((i + 1) + ". " + names[i]);
        }

    ____________________________________

10. What does this print?

        int[] scores = {55, 82, 91, 40, 76};
        ArrayList<Integer> passing = new ArrayList<>();
        for (int score : scores) {
            if (score >= 60) {
                passing.add(score);
            }
        }
        IO.println(passing);
        IO.println(passing.size());

    ____________________________________


WRITING CODE
------------

11. Complete the line so that it adds "Alan" to the end of the list:
    ArrayList<String> names = new ArrayList<>(List.of("Ada", "Grace"));
    names.__________________("Alan");
    IO.println(names); // [Ada, Grace, Alan]

12. Complete the line so that it sorts the copy, leaving scores as it
    was:
    ArrayList<Integer> scores = new ArrayList<>(List.of(88, 92, 79));
    ArrayList<Integer> ordered = new ArrayList<>(scores);
    __________________(ordered);
    IO.println(ordered + " " + scores); // [79, 88, 92] [88, 92, 79]

13. Complete the loop so that it keeps the even numbers:
    ArrayList<Integer> evens = new ArrayList<>();
    for (int n : numbers) {
        if (n % 2 == 0) {
            evens.__________________(n); // adds n to the end of evens
        }
    }


WHY IT WORKS
------------

14. Printing a shows [1, 2, 3, 4] even though only b was changed, because
    b = a does not create a second list: it makes b a second
    __________________ holding the __________________ object as a.

        ArrayList<Integer> a = new ArrayList<>(List.of(1, 2, 3));
        ArrayList<Integer> b = a;
        b.add(4);
        IO.println(a);

15. Collections.sort changes a list __________________ and gives back
    __________________, which is why
    ArrayList<Integer> result = Collections.sort(scores); does not
    compile.