Friday, March 11, 2011

Games Magazine: May Cover Maze

Robert Abbott, master of the logic maze, created the cover puzzle for the upcoming May 2011 issue of Games. In the original maze, there are four types of animal that can come in four different colors. You have to travel from the blue fox at the bottom to the blue chipmunk at the top by moving between pairs of animals. You can move any distance horizontally or vertically, but you can only end your move on an animal of the same type or color as the animal on which you started your move.

Bob has programmed a Java version of this maze which you can try at his site,

After Bob finished the design, he decided that he could make it more challenging by adding diagonal moves and increasing the size. Check out his site for an interactive version of this harder maze.

Thursday, March 10, 2011

Code-Breaking For Fun and Profit

Codes and ciphers are an area of puzzling that I haven't really written much about, but they've fascinated me since I first read Edgar Allan Poe's "The Gold Bug" as a child. As any history buff knows, cryptography and code-breaking has played a vital role in politics and warfare for at least 4000 years, and it has grown even more important in the digital age. Encryption is the key to the entire online economy. If it fails, the system fails.

Well, one small corner of the system has failed--spectacularly--and may have cost Microsoft at least $1.2 million.

All code breaking relies on the fact that everything, eventually, falls into a pattern, even if it's an incredibly complex--even shifting--pattern. Crack that pattern, and you crack the code. Modern computer cryptography is well beyond my knowledge set, but I do know that its relies on multiple branches of mathematics in order to create secure encryption keys.

But even the best keys have a pattern, and hackers have found the pattern for MS Points, the proprietary economy used by Xbox Live and other Microsoft services. People pay for games, multiplayer support, and in-game purchases with these points, which are normally purchased with real money.

MS Points are usually activated by entering a string of numbers and letters, and usually look something like H547J-3JK67-J84J0-etc...  Those numbers, however, are generated by a system, and that system has a pattern. Using old codes, some folks on the site The Tech Game (no, I'm not linking to it) discovered that pattern and created an algorithm to generate new, valid codes.

Microsoft isn't talking about this yet, but they've closed the exploit. We don't know yet if they'll be able to track down the scammers and take back their points. Of course, it's illegal and immoral, but it's a pretty impressive achievement. And a little bit terrifying.

By the way, let me veer slightly off-topic for a moment and just say that if you have a credit card with an RFID chip, get rid of it. Tech writers (including me) have been writing about the dangers of these chips for years. They are a hacker's dream. I've seen video of on-the-street tests of people using a few hundred dollars worth of equipment to read the credit card numbers from cards in people's wallets and purses. The RFID makers have implemented some pretty impressive cryptographic techniques in order to keep them secure, but one constant of computer security is the tendency to underestimate the determination and capability of hackers.

Wednesday, March 9, 2011

Over the Top: The World's Most Complex Rubik's Cube

I have never solved a Rubik's Cube, and never really tried. Thus, a Super-Sized Rubik's Cube, dubbed "Over the Top" by its inventor, holds even less appeal, particularly when it appears to take about a minute to align the parts correctly in order to make each turn.

A normal Rubik's Cube is 3x3x3. Designer Oskar van Deventer has used new 3D printing techniques and some impressive engineering to design one that is 17x17x17. You can even buy your very own version, for $2006.54, at Shapeways, a 3D printing company. Here's how it came to be, according the Shapeways
When Oskar heard of the world records being set for twisty puzzles, like the 7x7x7, 9x9x9 and 11x11x11 by Panagiotis Verdes from Greece, he wanted to try his hand at setting a new record himself. With sponsorship from his close friend Claus Wenicker, Oskar set about designing and testing a number of prototypes, and his third attempt was printed successfully with Shapeways. Sorting and dyeing all 1539 pieces took Oskar 10 hours of work, followed by 5 hours of assembling. The result is an oversized (140 millimeter, 5.5 inches) and fully functioning “Over The Top” 17x17x17 puzzle.
3D Printing is fascinating technology that allows anyone to create a viable 3D model, and then have it turned into a real object. Shapeways describes it as "any additive manufacturing process whereby one machine turns a digital file into a finished physical object by building up that object layer by layer. If you were to be more precise the technology would be called rapid manufacturing and 3D printing would just be one of the manufacturing processes used to create objects in this way."

These videos show Oskar explaining his amazing design. Frankly, the skill and technology that went into creating it is more interesting, to me, than the puzzle itself.

This is Shapeway's demo showing the entire process from design through completion:

Monday, March 7, 2011

Emily Dickinson's Puzzle Poems

Emily Dickinson's poetry is characterized by its highly compressed, idiosyncratic use of language to convey intense emotions. But she also wrote a series of light "riddle" poems in which the subject is never directly stated, leaving the reader to determine what the poem is about. They aren't difficult as riddles (except maybe for #1489), but they're important because of their use of language.

Here is the first, with the other three after the jump. I'll leave off the solutions for now in case readers want to solve them.

It sifts from Leaden Sieves --
It powders all the Wood.
It fills with Alabaster Wool
The Wrinkles of the Road --

It makes an Even Face
Of Mountain, and of Plain --
Unbroken Forehead from the East
Unto the East again --

It reaches to the Fence --
It wraps it Rail by Rail
Till it is lost in Fleeces --
It deals Celestial Vail

To Stump, and Stack -- and Stem --
A Summer's empty Room --
Acres of Joints, where Harvests were,
Recordless, but for them--

It Ruffles Wrists of Posts
As Ankles of a Queen --
Then stills its Artisans -- like Ghosts --
Denying they have been --

Lego Carcassonne

I've written about Lego Catan in the past, but someone has now taken it to the next level by working on a complex version Lego Carcasssonne. Designer Cal Henderson isn't actually making the whole thing, mind you, since a full set based on this design would cost around $2000 to create, but he's showing how it could be done.

A new computer mockup of Lego Catan was making the rounds of the interwebs last week. It looks great, but it hasn't been built.