Challenge 2: Context-Sensitive Return — Possible Solution
====================================================================

use strict;
use warnings;
use feature 'say';

sub get_letters {
    my @letters = ('a', 'b', 'c');

    if (wantarray()) {
        return @letters;
    } else {
        return scalar(@letters);
    }
}

my @all   = get_letters();
my $count = get_letters();

say "@all";
say $count;

Output:
a b c
3

WHY THIS WORKS AS AN ANSWER
------------------------------
This reuses the chapter's own get_scores example structure almost
exactly, with letters standing in for scores — wantarray() inside the
subroutine checks how get_letters was actually called by whoever
invoked it, per the chapter's own explanation, rather than the
subroutine's own code deciding in advance what to return.

my @all = get_letters(); assigns to an ARRAY, which puts the call in
LIST context (Chapter 3's own context rules apply identically to
subroutine calls, not just plain array assignment) — so wantarray()
returns true inside the subroutine, and return @letters; hands back
all three letters, which @all then receives in full.

my $count = get_letters(); assigns to a SCALAR instead, putting the
exact same call in SCALAR context — wantarray() now returns false,
and return scalar(@letters); hands back the element count (3) instead
of the letters themselves.

The subroutine's own code never changed between the two calls — only
the calling context did, and wantarray() is what lets the subroutine
detect and respond to that difference, exactly the "context-sensitive
return" the chapter names as Chapter 3's context theme "taken to its
logical extreme."