Discussion: The pros and cons to different approaches to solving a problem.

It's often the case that in academic and self-teaching environments, you don't really have the opportunity to grasp and fully understand situations in which a problem has multiple valid solutions and what the implications are in choosing among them. Among those considerations are two in particular: runtime efficiency and maintainability. When these subjects are discussed, the example solutions are often comical at best, or the problems themselves too complex to fully grasp the situation at hand. Sometimes the problems are also so simple as to be completely worthless, e.g. comparing bubble sort to bogo sort.

As such, I would like to take this opportunity to discuss practical but conceptually simple problems and the implications of the different solutions that are available. Conceptual simplicity is an absolute requirement because we want these problems to be accessible to a wider variety of readers. Problems don't necessarily need to be code-related (you could e.g. discuss something related to server administration). Bonus points for problems that include solutions with an efficiency/maintainability trade-off!