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Download now
[18th August 2002] This
ZIP file (35k)
contains a the C# code and HTML for the algorithm
and this site. It needs to be in a virtual directory
'Pontifex' on your web server.
About the code
Some of the code is based on the Java code available from
CounterPane. The Deck class implements
the IEnumerable interface in C#.
It was built using the Microsoft VisualStudio.NET Release Candidate
on Windows 2000 and Internet Explorer 6.0.
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About Solitaire (a.k.a. Pontifex)
August 2002
C# implementation of the Solitaire algorithm from
CounterPane
and featured in Neal Stephenson's book Cryptonomicon.
The code consists of the following classes:
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PontifexSolitaire |
exposes Encrypt() and Decrypt() methods that
use the Deck and Card classes to perform the Solitaire
algorithm on text strings |
| Deck |
class to model behaviour of cards in a deck, with
methods specific to the requirements of the Solitaire
algorithm (such as CutTop(), MoveDown(), TripleCut()...) |
| Card |
struct to model a card |
| CardFace |
enum [ Ace | Two ... Ten | Jack | Queen | King ] |
| CardSuit |
enum [ Hearts | Clubs | Diamonds | Spades | Joker ] |
This implementation is by no means the fastest, most efficient version of
the Solitaire algorithm; however I hope it's still interesting.
The design using Card and Deck objects is intended to make the code easy to read
and understand (and validate the algorithm logic against the text at
CounterPane).
The results from Counterpane's Solitaire test vectors
are also available to check.
You can test encrypt/decrypt strings using this
implementation, and check the results with
Carumba.org's Perl CGI implementation.
Finally, the Deck implementation provides a ToHtml() function (in addition to
ToString()) function which allows Deck testing.
There's really no great benefit to this, other than while constructing the
algorithm it was possible to test in parallel with a real deck of cards,
and visually check the results.
[Update 3rd March 2004]
Eli Robillard has blogged his (much nicer)
C# Implementation of the Solitaire (aka Pontifex) Encryption Algorithm which is definitely worth a look.
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Useful links
TRY IT OUT!
Encrypt and decrypt using Solitaire C# !
GotDotNet.com QuickStart
Read the .NET sample code, where I found the pieces for implementing IEnumerable.
CounterPane
Bruce Schneier of CounterPane is the designer of the Solitaire algorithm.
Carumba.org
A Perl implementation that you can try online.
Cryptonomicon
The book where I first read about Solitaire. Great book (other
Stephenson books are also recommended).
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