Knowledge-Based Approach of Connect-Four. The Game is Solved: White Wins

摘要

A Shannon C-type strategy program, VICTOR, is written for Connect-Four, based on nine strategic rules. Each of the rules is proven to be correct, implying that conclusions made by VICTOR are correct. Using VICTOR, strategic rules where found which can be used by Black to at least draw the game, on each 7 x (2n) board, provided that White does not start at the middle column, as well as on any 6 x (2n) board. In combination with conspiracy-number search, search tables and depth-first search, VICTOR was able to show that White can win on the standard 7 x 6 board. Using a database of approximately half a million positions, VICTOR can play real time against opponents on the 7 x 6 board, always winning with White.