A few years ago, a friend asked if I had any interesting problems he and a
coworker of his might enjoy.

This is one of the problems I gave them--the synchronized state machine
problem. My description of the problem can be found in the file "state.pdf".
This problem is also known as the firing squad problem, and is described
here on Wikipedia:

http://en.wikipedia.org/w/index.php?title=Firing_squad_synchronization_problem&oldid=462608569

This is not an easy problem, especially for people (like my friend) who have
not studied computer science. If you have not studied computer science, you
can be pleased with yourself if you are able to outline a solution of the
problem. If you actually produce a complete specification for the state
machines, you can be extremely pleased with yourself.

If you do go beyond outlining a solution and actually specify completely the
state machine, I've provided a simulator, in the directory "sim" that will
simulate the line of state machines so you can try out your solution and
see it work.

See the "README.txt" in the "sim" directory for instructions on building and
using the simulator.

The "doc" directory contains the source for the state.pdf file.

The contents of the "sim" directory are licensed under the 2-clause BSD
license. See the "LICENSE.txt" file in that directory for details.

The contents of the "doc" directory, and "state.pdf", are licensed under
the Creative Commons Attribution 3.0 Unported License. See "LICENSE.txt"
in the "doc" directory for more details.