Final answer:
The statement that a 'good array' is the smallest possible array consisting only of powers of two on HackerRank is false. Definitions such as 'good array' are specific to each problem on programming contest platforms and are not universally defined.
Step-by-step explanation:
The question asks whether for a number n, a "good array" is the smallest possible array that consists of only powers of two on the HackerRank platform. The statement provided is false. In many programming contests, including those on platforms like HackerRank, the definition of a "good array" or any such term would be provided in the context of a specific problem statement and is not a universally defined concept. It's important to read each question carefully as definitions can vary based on the problem at hand. Typically, a problem might define its own specific constraints and requirements for what constitutes a "good array".
Moreover, if a "good array" is specified by the problem to consist of only powers of two, there could be multiple arrays satisfying this criterion, not necessarily the smallest. Different problems might require different qualities in an array to be considered "good," and they may not always pertain to being the smallest possible array or even to powers of two.