A magic trick

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Introduction

While not a tool per se, this little "magic" program was inspired by a Web site that a friend sent me. I thought it neat enough to try and figure out how they did it. Within just a few minutes, a co-worker and I, with the help of a big whiteboard, figured out a solution. The result is a wizard-based dialog program that attempts to read your mind!

How to use

Following the on-screen instructions, it's self explanatory. Basically, you're going to jot down some numbers, scramble 'em up a bit, and the program will attempt to guess one of your numbers. If it guesses wrong, drop me a line and tell me the numbers you used. I may not have accounted for all exceptions.

The program is not fool-proof. It is possible to give it bogus numbers, and it will, in turn, give you a bogus answer. Making it totally fool-proof would have over-complicated the code, which I did once already.

The solution

I chose not to put a solution to the puzzle here, because then it would be way too easy for the casual Web surfer to find it, thus ruining any fun they might have had trying to figure it out the old fashioned way - using their head!

A solution is, however, in the code itself, and is very easy to comprehend (even easier when someone shows you how to simplify your math!). I would challenge you to try the program, or the referenced Web site, a few times before diving right in and looking at the solution.

References

• http://digicc.com/fido/
  
• Michel Wassink's static LED control
  
• It wasn't until I had this all put together that I learned the puzzle actually had a name. I found a very nice explanation of it here.

Improvements

The UI is a bit blah, but since my intent was not a flashy program, it matters not. One of these days, I might be so inclined to dress it up a bit. If you like drawing and GDI type stuff, feel free.