A Shannon C-type program which plays connect four perfectly


Velena Engine Source Code is free software; you can redistribute it and/or modify it under the following conditions:


This software is distributed in the hope that it will be useful, but without any warranty; including but not limited to implied warranties of merchantability or fitness for a particular purpose with respect to the software and accompanying written materials. The author takes no responsibility for use or misuse of this software. Although every effort has been made to produce a solid and efficient product the author cannot assure that the operation of the software will be uninterrupted and error free. The user takes every risk.

Actually the source code has been tested under Watcom C/C++ V10.0 and Linux gcc compiler.


During Velena development I have been helped by many persons:

This program is based on the knowledged approach of L.Victor Allis which designed and implemented a sophisticated AI engine in a program called Victor. Velena is basically the same, except that even newer concepts and techniques were introduced in order to reduce the problem complexity (of solving the game) to a more tractable factor of magnitude. Moreover Velena is available to anyone, while Victor (currently) is not. I thank L.Victor Allis for his support while I developed Velena and for the theory he made for solving Connect Four. Without him this program wouldn't have come to light.

I also thank Filippo Ghilardi who helped me to build the opening book data base which took several days of work on his Pentium 133 computer, and Davide Mazza who created the Velena intro logo (MSDOS version).

Click here to download Velena Engine Source Code V1.0

Any comments and suggestions are welcome

Giuliano Bertoletti