A friend just let me know about a 487-byte chess "engine". Don't expect FIDE compliance or search for this size! It will move into check for example; consider it a variant.
Your description of your program raises the question,
"How small can a chess engine be made which can correctly process every fide rule, including draw detection, underpromotion, e.p. capture, etc.?"
I guess that it cannot be done in under 1024 bytes.
I doubt there is a chess engine that includes draw detection for every chess position based on rule 5.2b(you can ask for draw detection for all the cases that are not covered by 5.2b)
For example it needs to detect a draw in the following position
[D]4kb2/8/8/p1p1p1p1/PpP1P1P1/1P6/2B5/1K6 w - - 1 1
relevant rule
The game is drawn when a position has arisen in which neither player can checkmate the opponent’s king with any series of legal moves. The game is said to end in a ‘dead position’. This immediately ends the game, provided that the move producing the position was in accordance with Article 3 and Articles 4.2 – 4.7.
Fantastic!! And without clever tricks
Congratulations
It has indeed search I also like the randomization so it never plays the same game twice...
Now this is truly incredible and so much better than BootChess, don't you feel pity now for the guys who wrote it?
bob wrote:Here is the smallest program that plays legal chess according to FIDE rules:
int main() {
printf("I offer a draw, accept? ");
scanf("%s", answer);
if (!strcmp(answer, "yes"))
exit 0;
printf("I resign\n");
}
This has been discussed before, but resigning is not 'playing chess'. It is actually exactly the opposite, namely the way to express that you are not prepared to play chess (anymore).
So the program you give here can only be said to "not play chess, in a FIDE-compliant way". Complying with FIDE rules does not automatically imply you are 'playing chess'. The FIDE rules for example also require you to shake hands before a game. That doesn't mean that shaking hands is playing chess...
Fantastic!! And without clever tricks
Congratulations
It has indeed search I also like the randomization so it never plays the same game twice...
Now this is truly incredible and so much better than BootChess, don't you feel pity now for the guys who wrote it?
Thanks! and errr, no, they didn't made enough effort. I would never put out a program with a bug so clear as putting its own king in check.
bob wrote:
Here is the smallest program that plays legal chess according to FIDE rules:
int main() {
printf("I offer a draw, accept? ");
scanf("%s", answer);
if (!strcmp(answer, "yes"))
exit 0;
printf("I resign\n");
}
That's funny Bob. But it's not legal to offer a draw before you've moved. So, you'd need to do something like, play 1.e4, then offer the draw.
Has anyone gotten BootChess to run in Linux? I installed DosBox and entering "dosbox" from ~/bootchess gives me a window showing the board but I can't enter moves.
Well, as mentioned before, watching a clock tick, resigning, not showing up at your game... None of that is playing Chess.
The empty program (zero characters) also complies with FIDE rules. Because FIDE rules do not compel anyone to play Chess. You can happily stay away from any Chess event, and FIDE will be perfectly happy.