Board Thread:Questions and Answers/@comment-1490123-20140731020450/@comment-5334617-20140731134139

The first '1' is not necessary. Regardless of how the number is represented, positive integer values in SmileBasic V2 always have 19 bits; and unspecified leading bits are always '0'.

If you want a bit for cliff edges, designate a bit for cliff edges. It's entirely up to you when the program checks the sense of the bits, and it's entirely up to you what the program does when it senses the bit is clear or set. If you're using someone else's code-base, it sounds like you'll have to learn how it works so that you can change it so it does what you want. If you're writing your own code, what you need to do is figure out exactly what you want to happen, and how to make it happen: but, there's nothing in the nature of bitwise representations and the AND operator to stop you.