Puzzle: Blue Block (aka Rush Hour)

Here's something lighter for this Friday.

I rediscovered a favorite game/puzzle in the iTunes store. It is called Blue Block (Free), created by Aragosoft, though I know this game as "Rush Hour."

I have shown this game to kids and adults alike and they've all liked it.

The goal is to 'free' the blue brick, which is blocked by white pieces. The white pieces can only slide in one direction, depending on their orientation. When you download, over 500 boards come free, in various levels of difficulty. The graphics is crisp, and it even tells you the 'par' which is the lowest number of moves to solve each board.

It's free. Give it a try.

The link, if you wish to download it to your iPhone/iPad:
http://itunes.apple.com/us/app/blue-block-free-unblock-sliding/id320111844?mt=8

I also found online versions of the game:
http://www.freegames.ws/games/freegames/cargames/rushhour.htm
or
http://www.freeonlinegames.com/puzzle-games/gridlock.html (with pop-ups, unfortunately)

Extra:
For those of you who want to think about the game more (after playing it for a few rounds):
If someone asked you to 'program' the solution to this game, how would you go about formulating it? I can think of a few possibilities: Dynamic programming, using arcs-and-nodes and state-diagrams, and as an Integer Program (IP). For the IP, it is tricky to come up with an elegant objective function.

Would love to hear your thoughts on programming or solving it. Leave comments or drop me an email.


Related Posts:
Flood-It
Loop The Loop aka Fences