Reusing Active Yeast for another batch?

Hello all, I currently have some Octoberfest beer brewing and was wondering when it is done, could I pour the wort for a Stout INTO the container that held the Octoberfest to use the yeast that's currently active in there?

Or is it best to just start from scratch?

I figured (and please correct me if I am wrong) that reusing yeast from a previous batch was ok as long as the beer that finished coming out, came out ok? I realize that this MAY impart some flavor into the new Stout.

Pro's/Con's?

Thank you in advance.

That's referred to as pitching onto the cake, and it would be okay. You could also rinse the yeast in there as well, but if you're lazy like me, pitching on top is fine. What's the yeast strain?

Thank you for the reply, it's just regular dry yeast from Mr. Beer. Cheers!