Challenge 3: A Bounded Generic smaller() Method — Possible Solution
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BoundedDemo.java:

public class BoundedDemo {
    public static <T extends Comparable<T>> T smaller(T a, T b) {
        return a.compareTo(b) < 0 ? a : b;
    }

    public static void main(String[] args) {
        System.out.println(smaller(7, 3));
        System.out.println(smaller("banana", "apple"));
    }
}

Output:

    3
    apple

Explanation:
`T extends Comparable<T>` restricts T to only those types that
implement Comparable<T> -- both Integer (via autoboxing, java1-2) and
String satisfy this, since both provide a real compareTo() method.
Because of that bound, the compiler can verify a.compareTo(b) is a
legitimate call at compile time, for ANY type T is eventually filled
in with -- it doesn't need to wait until runtime to find out whether
compareTo() exists, and it would reject a type that doesn't implement
Comparable<T> before the code ever runs.

WHY THIS WORKS AS AN ANSWER
------------------------------
This uses the exact bounded-type-parameter pattern the chapter
introduces, and demonstrates it working correctly with two genuinely
different types (Integer and String), showing the compile-time safety
the bound provides despite erasure still applying underneath.