n! can be improved upon; TSP can be done in n^2 * 2^n space and (I think) n^3 * 2^n time, though that's obviously impractical for any large n.

IIRC, anybody who's going to be pointing lasers into the air is supposed to file notice with the FAA; the FAA will notify any pilots who file a flight plan to avoid that area. A stage show will file the permits; small groups may fail to do so.

I thought that they generally didn't want lawyers on juries anyway.

I'm reminded of a story from the Crimean War:

A soldier wrote to his family "Go to _____ store in London, buy me some maps of the Crimea and send them out here. They have better maps than the army gives us."

It's possible to do better than O(N!); there's a straightforward O(N*2^N) algorithm.

What happens when x == -1?

IIRC, if you're using direct current, hydrogen and oxygen are produced at opposite ends of the wire. So separating them is automatic.

Waterclap

Odd. The usual example for judicial notice involves a defense attorney using a Farmer's Almanac to put the phase of moon into evidence, and discredit a witness.

Anybody who disables it and gets caught will go to jail.