Ran into bug - AI beat me by creating a diagonal with the piece in the top rank and it did not count that as endgame. I was able to keep playing.
Should be fixed now - an off by one error checking diagonals that hit the top of the board. Thanks!
Play against the computer – Connect Four game in JavaScript
21–26 of 26 posts
Re: Play against the computer – Connect Four game in JavaScript
#22ICYI Connect Four is a solved game, you can read about it here: https://en.wikipedia.org/wiki/Connect_Four#Mathematical_solu...
Yes, I may do a minimax version with a difficulty setting. That would be fun to do.
If you tell the optimal algorithm to only think 3 moves ahead, it's too easy, and if you let it think 4 ahead it becomes very difficult (but not quite impossible).
Re: Play against the computer – Connect Four game in JavaScript
#23Earlier quoted context omitted.
It seems like going first is a disadvantage, since the AI can just play defensively until you are backed into a corner.
I've found that the only way to win is to go first, just like in tic tac toe. Going second can produce a draw at best, against an optimal opponent. This is just my experience though, not a strong assertion.
This is not true, I've played twice as the second player and won both. The seem to likes setting up 3 diagonal, during that you are free to setup your own lower trap with two intersecting diagonals. So far doing that always seems to win.
Re: Play against the computer – Connect Four game in JavaScript
#24The best trick I can think of is to reach a point where you can get connect four in two or more places and the bot can only cancel out one.
Re: Play against the computer – Connect Four game in JavaScript
#25ICYI Connect Four is a solved game, you can read about it here: https://en.wikipedia.org/wiki/Connect_Four#Mathematical_solu...
You can solve it yourself from scratch in a few minutes by running my Fhourstones benchmark [1]. Other interesting connect-4 tidbits may be found on my connect-4 page [2].
Re: Play against the computer – Connect Four game in JavaScript
#26Thanks for sharing! This sent me down the solvability path. It would be cool to have an ‘expert’ mode that plays the optimal strategy.
Your wish has been granted: https://connect4.gamesolver.org/