GMAT Math

So when OG problem 61 for DS asks how many integers are between, but not including, r and s, when s - r = 10, I said it wasn't sufficient because I didn't know what integers would be between them just because the range was provided.

I was thinking the numbers could be something like:

0 1 2 2 5 7 10

Or any other unlimited combination.

So of course, the problem intended that it was all the integers between them as if you were counting, so none would repeat or skip or anything like that. Doh!