Quote Originally Posted by Salem View Post
If the user can enter "FB", then what (other than an array) would you store them in?

Sure you can read "F" and then "B" (in either order), but that would mean a loop.

Your requirements are so hopelessly constrained (don't use any obvious things) to the point that it seems more like an exercise to discover the tutor's stupid magic trick rather than teaching any useful programming skills.
Yeah, that's true. Besides array and looping, I can't think of a way to make this magic happened. So just asking around see if make sense, haha.