cblocks provides the user with a chance to play sliding-block puzzles
on the Linux console. The object of each game is to slide the blocks
into their final destination. The blocks cannot be picked up or turned
around; they can only slide into an unoccupied space. This
distribution comes with ten puzzles included; more can be easily
added.
INSTALLING
To support the mouse, you will need to have the gpm library installed,
as well as the include file gpm.h. Alternately, you can build the
program without mouse support by including the --disable-mouse option
when running ./configure at the top-level directory.
An alternate version of cblocks is included, which uses ncurses and
therefore does not require the Linux console. It isn't quite as
pretty, and lacks the highly useful mouse support, but otherwise it
has all the same functionality. To build this version, include the
--with-ncurses option when running ./configure at the top-level
directory.
By default, the executable is copied to /usr/local/games and the data
files are copied to /usr/local/share/cblocks.
BACKGROUND
Sliding-block puzzles apparently came into being soon after Sam Loyd's
14-15 puzzle attained such popularity. These puzzles expanded on the
original idea by using pieces of different shapes. Unlike the 14-15
puzzle, the theory of which was worked out relatively quickly, most
sliding-block puzzles are quite difficult to analyze mathematically.
They therefore become puzzles that challenge our intuition, and
eventually yield to insight into their peculiar internal logic.
The first few puzzles that come with this distribution are early
examples of the genre, and should provide the user with a good
introduction. The fourth puzzle is probably the first canonical
example of a sliding-block puzzle, and should give the novice user a
good bit of trouble to solve. It was originally marketed as "The
Penant Puzzle". Each block bore the name of a major city, with the
large block being the home team. The large block is therefore to be
maneuvered past the others and into first place. Since then, it has
been marketed under several guises. The most successful was under the
name "Dad's Puzzler", with the blocks representing different pieces of
furniture in a crowded room, the large block being a grand piano that
needed to be moved to their other side. The name "Dad's Puzzle" is
what it has now become generally known by.
Probably the puzzle that most people will have seen before is the
eighth one in this collection: "L'Ane Rouge", or The Red Donkey (and
many other names since). It is listed as first being marketed in 1946,
although Martin Gardner reports others having seen it or some version
of it in the 1930s. It is signifcantly more difficult than Dad's
Puzzle, and solving it should whet the user's appetite for more.
Two puzzles in this collection do not come from the early 20th
century: the Century Puzzle and the Century-and-a-Half Puzzle. John
Conway introduced these in "Winning Ways". The Century Puzzle was
found from doing a mathematical search for the hardest puzzle of the
same genre as L'Ane Rouge. The Century-and-a-Half Puzzle begins the
same as the Century Puzzle, but continues on until all the pieces
until the puzzle has been turned upside-down.
REFERENCES
Gardner, Martin: "Martin Gardner's Sixth Book of Mathematical
Diversions from Scientific American", chapter 7. As is often the case,
Martin Gardner provides one of the earliest written descriptions of
this genre and its history.
Berlekamp, Elwyn; Conway, John; and Guy, Richard: "Winning Ways,
volume 2", chapter 24. Berlekamp, Conway, and Guy provide a complete
analysis of Dad's Puzzle, L'Ane Rouge, and the Century Puzzle.
Hordern, Edward: "Sliding-Piece Puzzles". The definitive book on the
subject, apparently. (If anyone out there can provide me with a copy of
this book, I will gladly pay a finder's fee.)
: "Nick Baxter's
Sliding-Block Puzzle Page". Nick Baxter's wonderful page has many more
puzzles available, playable via a Java applet.
Brian Raiter
September, 2000