kiwipete perft position
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Re: kiwipete perft position
By the way perft(4) = 4085603 for kiwipete position in Skipper so case closed.
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Re: kiwipete perft position
kiwipete is a good test position, but it is by no means complete. I would look at the link earlier and test all of them to make sure you have all the edge cases covered.
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Re: kiwipete perft position
Skipper gives castling rights depending on rook number. So the position below might give a problem. Skipper gives perft(4) = 265703
[d] rrrrkr1r/rr1rr3/8/8/8/8/8/6KR w k - 0 1
[d] rrrrkr1r/rr1rr3/8/8/8/8/8/6KR w k - 0 1
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Re: kiwipete perft position
ai. stockfish_14053109_x64_modern.exe gives 266260Henk wrote:Skipper gives castling rights depending on rook number. So the position below might give a problem. Skipper gives perft(4) = 265703
[d] rrrrkr1r/rr1rr3/8/8/8/8/8/6KR w k - 0 1
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Re: kiwipete perft position
Enough of it. I have to rewrite it all. Rook numbers make no sense and should be removed. Only thing that matters if black or white can castle short or long.Henk wrote:ai. stockfish_14053109_x64_modern.exe gives 266260Henk wrote:Skipper gives castling rights depending on rook number. So the position below might give a problem. Skipper gives perft(4) = 265703
[d] rrrrkr1r/rr1rr3/8/8/8/8/8/6KR w k - 0 1
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Re: kiwipete perft position
Mine agrees with SF:Henk wrote:Enough of it. I have to rewrite it all. Rook numbers make no sense and should be removed. Only thing that matters if black or white can castle short or long.Henk wrote:ai. stockfish_14053109_x64_modern.exe gives 266260Henk wrote:Skipper gives castling rights depending on rook number. So the position below might give a problem. Skipper gives perft(4) = 265703
[d] rrrrkr1r/rr1rr3/8/8/8/8/8/6KR w k - 0 1
Code: Select all
FEN string = rrrrkr1r/rr1rr3/8/8/8/8/8/6KR w k -
Depth = 4
Leaf nodes = 266260
Time taken = 10 ms
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Re: kiwipete perft position
Yes but the author does not change. So it might become crap again sooner or later.zullil wrote:Mine agrees with SF:Henk wrote:Enough of it. I have to rewrite it all. Rook numbers make no sense and should be removed. Only thing that matters if black or white can castle short or long.Henk wrote:ai. stockfish_14053109_x64_modern.exe gives 266260Henk wrote:Skipper gives castling rights depending on rook number. So the position below might give a problem. Skipper gives perft(4) = 265703
[d] rrrrkr1r/rr1rr3/8/8/8/8/8/6KR w k - 0 1Yes, starting Skipper over from scratch seems sensible. Sounds like your entire design is needlessly complicated.Code: Select all
FEN string = rrrrkr1r/rr1rr3/8/8/8/8/8/6KR w k - Depth = 4 Leaf nodes = 266260 Time taken = 10 ms
When computing perft(3) after Rh1-h2 Skipper gives wrong perft(2) after Rf8-f1 that is 106. But if I compute the perft(2) from the fen of the position after Rh1-h2, Rf8-f1 it gives 108 which is ok. riddle riddle.
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Re: kiwipete perft position
So in this position according to Skipper perft(3) = 37159 which should be 37239. And perft divide (3) gives 106 after f8-f1 which should be 108.
[d] rrrrkr1r/rr1rr3/8/8/8/8/7R/6K1 b k - 0
But in the position below Skipper computes perf(2) = 108 ?? Which is correct.
[d] rrrrk2r/rr1rr3/8/8/8/8/7R/5rK1 w k - 0 1
So perhaps after f8-f1 Skipper still thinks it can't castle short when it uses the fen of the first position,
[d] rrrrkr1r/rr1rr3/8/8/8/8/7R/6K1 b k - 0
But in the position below Skipper computes perf(2) = 108 ?? Which is correct.
[d] rrrrk2r/rr1rr3/8/8/8/8/7R/5rK1 w k - 0 1
So perhaps after f8-f1 Skipper still thinks it can't castle short when it uses the fen of the first position,
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Position with eleven rocks.
Hello:
I hope no typos. Good luck with your debug!
Regards from Spain.
Ajedrecista.
Henk wrote:Skipper gives castling rights depending on rook number. So the position below might give a problem. Skipper gives perft(4) = 265703
[d] rrrrkr1r/rr1rr3/8/8/8/8/8/6KR w k - 0 1
Code: Select all
rrrrkr1r/rr1rr3/8/8/8/8/8/6KR w k - 0 1
Results by JetChess 1.0.0.0:
perft(1) = 8
perft(2) = 388
perft(3) = 4,827
perft(4) = 266,260
perft(5) = 2,955,677
perft(6) = 174,627,748
perft(7) = 1,941,335,854
perft(8) = 120,165,734,022
perft(9) = 1,335,631,917,716
Regards from Spain.
Ajedrecista.
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Re: kiwipete perft position
That's an interesting position. My freshly implemented perft worked for all positions on the cpw except this one where on perft 4 it gave exactly 4 nodes too many which seemed like an oddly small number to be off.
As it turns out I somehow didn't clear e.p. rights when castling which gave the exact line 1.a4 either castling 2.either castling bxa4 e.p. for 4 extra nodes...
As it turns out I somehow didn't clear e.p. rights when castling which gave the exact line 1.a4 either castling 2.either castling bxa4 e.p. for 4 extra nodes...