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Does it cover all the possibilities? Has someone done a better one already? Any suggested changes?
[d]r3k2r/1bp2pP1/5n2/1P1Q4/1pPq4/5N2/1B1P2p1/R3K2R b KQkq c3 0 1
Thanks

Michael Sherwin wrote: ↑Sun Apr 21, 2019 5:10 am Does it cover all the possibilities? Has someone done a better one already? Any suggested changes?
[d]r3k2r/1bp2pP1/5n2/1P1Q4/1pPq4/5N2/1B1P2p1/R3K2R b KQkq c3 0 1
Thanks

nice one. pins are an important source of bugs. you should add more pins.

lucasart wrote: ↑Sun Apr 21, 2019 7:12 am

Michael Sherwin wrote: ↑Sun Apr 21, 2019 5:10 am Does it cover all the possibilities? Has someone done a better one already? Any suggested changes?
[d]r3k2r/1bp2pP1/5n2/1P1Q4/1pPq4/5N2/1B1P2p1/R3K2R b KQkq c3 0 1
Thanks

nice one. pins are an important source of bugs. you should add more pins.

Bed time, I will work on that tomorrow!

Sapeli says:

./sapeli -position fen r3k2r/1bp2pP1/5n2/1P1Q4/1pPq4/5N2/1B1P2p1/R3K2R b KQkq c3 0 1 -perft 6
depth 0 nodes 1 mnps 0.000 time 0.000
depth 1 nodes 60 mnps 0.000 time 0.000
depth 2 nodes 2608 mnps 0.000 time 0.000
depth 3 nodes 113742 mnps 14.218 time 0.008
depth 4 nodes 4812099 mnps 13.256 time 0.363
depth 5 nodes 202902054 mnps 13.964 time 14.530
###
nodes 207830564 mnps 14.304 time 14.530

Michael Sherwin wrote: ↑Sun Apr 21, 2019 8:29 am

lucasart wrote: ↑Sun Apr 21, 2019 7:12 am

Michael Sherwin wrote: ↑Sun Apr 21, 2019 5:10 am Does it cover all the possibilities? Has someone done a better one already? Any suggested changes?
[d]r3k2r/1bp2pP1/5n2/1P1Q4/1pPq4/5N2/1B1P2p1/R3K2R b KQkq c3 0 1
Thanks

nice one. pins are an important source of bugs. you should add more pins.

Bed time, I will work on that tomorrow!

How aboud this?
[D] r6r/1bp2pP1/R2qkn2/1P6/1pPQ4/1B3N2/1B1P2p1/4K2R b KQ c3 0
It adds pins of the 2 possible kinds:
* the normal pin, where from->to causes self-check through the vacated from square.
* the en-passant special case, where from->to causes self-check, through the square vacated by the captured enemy pawn.

There is actually a third kind of pin, but that only happens in Chess960. It's when you can't castle, because the castling rook is pinned.

Michael Sherwin wrote: ↑Sun Apr 21, 2019 5:10 am Does it cover all the possibilities? Has someone done a better one already? Any suggested changes?

[d]r3k2r/1bp2pP1/5n2/1P1Q4/1pPq4/5N2/1B1P2p1/R1R1K2R b KQkq c3 0 1
After Rxa1 Rxa1 you have rook on A1 that has already moved so castling is impossible. But no rook has ever moved away from A1.

if my engine is not wrong those are the results:
1: 60
2: 2608
3: 113742
4: 4812099
5: 202902054
6: 8419356881

another possibile source of problem is the interaction of "pin" and en passant. I think this is rare but it can happen.
here an example where en passant capture is forbidden (fxe3)
[d]8/K7/8/8/2Q1Pp1k/8/8/8 b - e3 0 1

elcabesa wrote: ↑Sun Apr 21, 2019 10:31 am if my engine is not wrong those are the results:
1: 60
2: 2608
3: 113742
4: 4812099
5: 202902054
6: 8419356881

Sorry, but your engine is wrong. Perft 2 of the position "r3k2r/1bp2pP1/5n2/1P1Q4/1pPq4/5N2/1B1P2p1/R1R1K2R b KQkq c3 0 1"is 2659.

Maarten Claessens wrote: ↑Sun Apr 21, 2019 11:31 am

elcabesa wrote: ↑Sun Apr 21, 2019 10:31 am if my engine is not wrong those are the results:
1: 60
2: 2608
3: 113742
4: 4812099
5: 202902054
6: 8419356881

Sorry, but your engine is wrong. Perft 2 of the position "r3k2r/1bp2pP1/5n2/1P1Q4/1pPq4/5N2/1B1P2p1/R1R1K2R b KQkq c3 0 1"is 2659.

Well if you mistype the FEN and search a different position...