function is it computing in you know inside this little description so the canonical example of this is a circuit satisfiability problem also known as circuit set okay it's really like the simplest circuit analysis problem in a particular sense here you're given a logical circuit see so you wrote you've written down some description of some circuits got wired together in some funky way and you want to know is it computing the all zeroes function is it the case that no matter what input I give it is always going to print zero or