Challenge 2: power With a Default Exponent — Possible Solution
====================================================================

#include <iostream>

int power(int base, int exponent = 2) {
    int result = 1;
    for (int i = 0; i < exponent; i++) {
        result *= base;
    }
    return result;
}

int main() {
    std::cout << power(3, 3) << std::endl;  // both arguments given
    std::cout << power(5) << std::endl;     // default exponent used
    return 0;
}

Output:

    27
    25

WHY THIS WORKS AS AN ANSWER
------------------------------
power(3, 3) explicitly overrides the default, computing 3^3 = 27.
power(5) omits the trailing exponent argument entirely, so the
compiler substitutes the declared default value (2), computing
5^2 = 25 -- exactly the chapter's own pattern of a trailing parameter
being safely omittable because it has a default.