Domanda di colloquio di Epic

Programming question: Write an algorithm that, when given an integer, will produce all the possible combinations of that length integer. All digits will be alphabetical, either uppercase or lowercase. It provided the ASCII number equivalents for them as well. However, the combination must be in order and unique. For example, k=3. Accepted: abc, abd, abz, aBc, ABc. Not Accepted: aZd aDd, Bza, etc. You need to write a function that produces all possible strings based on the above criteria. This was one of the four programming questions on the assessment.