\b[Permitted; returns `"C"`.] Both receiver and argument have <static type> `C`, so the most-specific applicable overload is `show(C)`. That method is defined in `C` and returns its own one-letter result without calling `super`. The six results, in source order, are therefore \b[`AB, AB, AB, BC, BC, C`].

Solution

Past exam of the year 1 of the computer science course of the University of Oxford / 2023 / Imperative programming / 6 / b / vi / Solution

 Solution (source code)