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MatPlus.Net Forum Competitions Sake 2023
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(1) Posted by Georgy Evseev [Tuesday, Aug 22, 2023 09:41]

Sake 2023

Clarifications of condition required.

1. Can the pawn promoted with capture continue movement as a promoted piece, or it has to stop when promoted?
2. When the captured pieces are removed from board? for example, is the following move allowed: Be3xf4xg5-c1 (going through f4 where the unit was initially)?
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(2) Posted by Joost de Heer [Tuesday, Aug 22, 2023 10:55]

I assume Thomas implemented the definition that the inventor wanted.

pie whi ka1 pa7
bla ka8 rb8
stip ~1
cond seriescap

1.Ka1-a2 !
1.a7*b8=Q + !
1.a7*b8=S !
1.a7*b8=S-a6 !
1.a7*b8=S-c6 !
1.a7*b8=S-d7 !
[etc etc]

pie whi bc1 ke1
bla kh8 pe3 pf4
stip ~1
cond seriescap

1.Bc1*e3 !
1.Bc1*e3-c1 !
1.Bc1*e3-d2 !
1.Bc1*e3-g1 !
1.Bc1*e3-f2 !
1.Bc1*e3*f4 !
1.Bc1*e3*f4-c1 !
1.Bc1*e3*f4-d2 !
1.Bc1*e3*f4-e3 !
[etc etc]
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(3) Posted by shankar ram [Tuesday, Aug 22, 2023 11:04]

Tests with the new 4.89 version of Popeye confirms that both cases are possible:

A pawn after a promotion with capture can make an additional move or capture.

A piece can pass through its original square, after a series of captures.

A piece can even return to its original square, after a series of captures!
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(4) Posted by Joost de Heer [Tuesday, Aug 22, 2023 12:05]

I think SeriesCaptures will be the first condition where a '=1' will be unsolvable by Popeye. is an =1 with SeriesCapture.
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(5) Posted by Thomas Maeder [Wednesday, Aug 23, 2023 05:37]

I think that most questions about the basic properties of the condition are answered by the test cases in the following file:
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(6) Posted by Joost de Heer [Wednesday, Aug 23, 2023 07:34]

w: Pa2 Pc2
b: Pb3
Series-Capture, Andernach

Colour is just a property, so why wouldn't white be able to play a2xb3[=b]xc2[=w]-c4? The definition only mentions 'the moving piece can make another movement', it doesn't stipulate that the colour of the moving piece must remain the same.
When a half-neutral piece moves, is the colour changed at the end of the capture sequence, of after every capture?
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(7) Posted by Kevin Begley [Wednesday, Aug 23, 2023 21:51]


Color is more than a property of the unit.
Color defines move alternation of players, color defines which player can move a given unit, and color defines which units can be captured (both by a given unit and by a given player with the move).

You are suggesting that an Series-Capture + Andernach Unit, by default, should be allowed to continue making captures, despite the fact that:
1) the player on the move would be capturing units that this player can not (by default) legally capture, and
2) the player on the move would be making those captures by moving a unit which has changed to a color which that player can not (by default) legally move.

I will admit, this is one possible interpretation of this combination of fairy conditions, and this is a very interesting interpretation.
But, why should this be the default rule?

More specifically:
1) why presume that this combination of conditions inherently allows a player to capture units of their own color (that generally would require a separate fairy condition)? and
2) why presume that this combination of conditions inherently allows a player to move units of a color they are not allowed to move (again, that generally would require a separate fairy condition)?

Neither of these two conditions, when taken by themselves, would be defined in such a way that suggests your interpretation (which transcends default move alternation, which transcends default capturing rights).
You are somehow deducing that the combination of these two conditions must imply a completely new set of rules, and this should be the default.

The Andernach condition (and also the Anti-Andernach condition) does not inherently suggest that the black player, in a series-help problem, should be allowed to continue moving a unit which has changed colors (to a color they are not permitted to move). You can not argue, oh come on, the black player moved that unit before, and color is just some meaningless attribute of the unit.
Color attributes matter! (sorry, LOL, I couldn't resist).

Furthermore, Series-Capture does not inherently suggest this should be its default.
Your interpretation is very interesting, and I'd love to see it implemented, but this should require either an additional fairy condition (possibly two), or (at the very least) it should require an additional attribute of the series-capture condition.
Otherwise, you are unnecessarily complicating the definition of Series-Capture (which should default to the simplest possible expression).

Is this the default for T&M + Andernach?
I sincerely hope the combination of those two conditions does not result in color changes prior to rebirth (which then alter the rebirth direction), but I fear the mere inquiry into the default of that combination is likely to be taken as an invitation for more chaos and inconsistency.
I have no problem enabling varying interpretations (we should welcome more deviation from the imposition of arbitrary default rules), and I would prefer to avoid the territorial struggle for dominance which comes with every disagreement over which arbitrary choices should be the default, but we do need to establish a consistent expression for these alternative options and we do want a coherent system which does not burden our audience to recall (or lookup) the arbitrary default rules.

We should not require the audience to read the fine print to understand that the Series-Capture condition alters the rules of move alternation when combined with the Andernach condition (the same can be said of paralyzing units, which alter the definition of stalemate -- a fact the audience only learns if they read the fine print).

If you need a doctorate in fairy conditions to interpret the rules laid out by the composer, your artform can be considered a ridiculous failure.
What kind of lazy, illogical, careless artist colony would burden their own audience (including the new arrivals they are hoping will join, they are hoping will carry on their legacy) to learn all their ridiculous inconsistencies?

The answer is actually quite clear: the people who do this are more interested in territorial dominance than in continuing the legacy of this artform.

The burden should be upon the composer to clearly express (in their fairy condition listing) any deviation from normalcy.
If there is no consistent default which applies to ALL fairy conditions, this burden must fall on all sides of the arbitrary decision.

What does this mean?
If the problem community refuses to make Rex Inclusive the default spanning all conditions (including retroactively), then the composer must always mention it (you can not bury this arbitrary default within the fine print of the condition's rules).
Similarly, if the problem community refuses to make Rex Exclusive the default spanning all conditions (including retroactively), then the composer must always mention it.

The actual default for all conditions should be those problems which are valid under all arbitrary rules (if your problem is valid under both Rex Inclusive AND Rex Exclusive, you need mention neither). Otherwise, the burden is on you, dear composer -- you owe it to your audience to spell out the rules.
The audience should not allow composers to express arbitrary rules within the fine print of each condition used.

Composers have too long burdened their audience (especially solvers) to recall (or lookup) the arbitrary biases of a thousand chaotic fairy inventors.
If the problem community can't provide a consistent set of arbitrary defaults which span all conditions, the burden falls upon all composers to resolve the matter.
If composers will not take responsibility, and alleviate the burden of their audience, let their disgraceful failures be displayed in the fairy condition listings of their every problem.

If you want to encourage newcomers to enjoy (and solve) fairy problems, unburden your audience from reading the fine print for your every fairy condition.
It is the composer's burden to clearly express the rules of their problem (they can not ignore that responsibility by pointing to the fine print of a fairy condition with complexity deliberately heaved upon it, so it might conceal the inelegance of the composer).

Too long have composers been looking out for their own interests, rather than the best interests of this artform (they have proved, time and again, untrustworthy in establishing their own rules).
Hint: a needlessly burdened audience is not in the long-term interest of your artform.

The problem community should establish a consistent set of defaults which retroactively apply to ALL fairy conditions.
Either Rex Inclusive should always be the default, or Rex Exclusive should always be the default. I'll leave that arbitrary choice for the problem community -- I'm not looking to advance my own biases, nor to assert my own dominance, only to advance the best interests of this artform.

If composers establish a consistent set of default rules for these arbitrary cases, retroactively assuring that these defaults span ALL fairy elements, you will greatly unburden yourselves and your audience.
Furthermore, the combination of your conditions will more readily connect.If there is one default rule for pawns which appear on their first rank, and any deviation must be stated as a separate fairy condition, then you'll have fewer problems when a pawn appears on the first rank in a problem where you have combined Point Reflection + Parrain Circe + Einstein conditions). You'll not need to rely on the ordering of these three conditions to determine priority (I can assure you, that methodology is grossly insufficient to resolve the issues in this case).

If composers refuse to resolve these matters, their problems should be reprinted by publications which will properly list the full set of fairy conditions they have actually employed.
If that doesn't shame them into action, you can safely say this artform is dying.

I was recently reminded how deeply the Shogi community cared about their game. Centuries of enthusiasts were continually bettering it. That level of devotion, spanning generations, is why Shogi has endured.
If fairy chess problem composers today don't even care enough to unburden their audience from the impositions of their the needlessly chaotic arbitrary inconsistencies, they must not have a legacy worthy of preservation. They care deeply about preserving their titles, but not their artform.

Very few of our titled enthusiasts can even define the color attribute of a unit.
Ask a titled composer to explain why the Bicolores fairy condition isn't a color attribute of the unit.

If we establish clear definitions for the fundamental elements of our problems, and the fundamentals of our units, most of our inconsistencies will resolve themselves.
If this community doesn't care enough to fight to preserve its legacy, we should all consider learning Shogi.
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(8) Posted by Joost de Heer [Thursday, Aug 24, 2023 07:24]

If a piece is reborn, does it become a different piece? Apparently not, because a reborn anticirce piece can continue the capture series
If a piece is recoloured, does it become a different piece? Apparently, because a recoloured piece cannot continue the capture series.

IMO the piece stays the same, only a property (square or colour) changes.
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(9) Posted by Kevin Begley [Thursday, Aug 24, 2023 16:08]

By default, the white player can legally move a white Rook which has changed position (by Circe transmogrification).
By default, the white player can NOT legally move a white Rook which has changed color (by Andernach transmogrification).

Are they the same unit? That's a very deep philosophical question.
For brevity's sake, I'll not touch that.

Should your very interesting interpretation be the default? No. Never.
The default for the Series-Capture condition should not allow the white player to continue making a series of moves with a rook which has changed to a color that the white player can not, by default, move (capturing units of a color that the white player can not, by default, capture).

The interpretation you are describing is better handled as a couple of fairy conditions firing at the same time (or, at the very least, it should require a special attribute to the Series-Capture condition). It would be a very unexpected behavior for a condition intended to provide a series movement option to the capturing unit to override move alternation rules, by default, when color changes are possible.

As such, it would be completely improper to add some fine print to the definition of the Series-Capture condition, allowing for this completely unexpected behavior when coupled with the Anderernach condition (and then burden your audience to know this rule, which is buried in the fine print).

The composer is attempting to push their burden (it's their responsibility to clearly express the rules of their problem) onto the audience (read: solvers would require a doctorate in the fine print of fairy chess rules, so that the composer can deceive the audience into believing their expression is elegant).
note: there is nothing elegant about unexpected behaviors justified by fine print.

Further, this chaotic precedent would only invite (if not encourage) further disasters.
-T&M would soon require some fine print allowing unexpected behaviors when coupled with Andernach.
-Duelist would soon require some fine print compelling the white player to continue moving a unit which has changed colors to black (too bad if you have no legal move with that unit -- Joost's interpretation asserts that it's still the same unit; thus, by the default expressed in the fine print definition, you must continue moving that same unit, unto annihilation or stalemate; in fact, why shouldn't the rules of stalemate also be suspended/altered, by default, to allow continuous movement of that same unit?).
-And the hits just keep on coming.

Your rule interpretation (allowing the unit to keep capturing, and ignoring color changes entirely) is very interesting, but it would be a very bad idea to make this unexpected behavior the default rule for the Series-Capture condition, and then bury that default rule in the fine print of a definition for a condition which nobody would ever suspect allows a white player to capture a white pawn with a black rook.

That said, if history is any indicator, there's a very good chance the problem community will prefer more chaos, more inconsistency, and the path which maximizes the burden upon our audience (read: more fine print).

Because, hey, why should we composers not enjoy the decadence?
Let's pass around some problems made while on drugs, and let the audience worry about the fine print.

"Physical reality is consistent with universal laws. Where the laws do not operate, there is no reality. All of this is unreal." -- Mr. Spock.
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(10) Posted by Andrew Buchanan [Tuesday, Aug 29, 2023 06:03]

I found what I think is a bug in the Popeye implementation:

fors rsbqkbsr/p1pppppp/1P6/8/8/8/1PPPPPPP/RSBQKBSR
stip dia1.5
cond seri

Popeye gives no solution but it should be 1.a4 b5 2.axb5-b6.

Mu-Tsun Tsai has kindly posted in github, and it may need to be fast-tracked for resolution.

He notes that the position after 1...b5 with stip ~1, does list 2.axb5-b6 as a legal move.

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(11) Posted by Thomas Maeder [Tuesday, Aug 29, 2023 07:02]

I assume that it's a proof game "optimization" that I forgot to disable for SeriesCapture problems.

Only problems with goal dia or A=>B should be affected.
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MatPlus.Net Forum Competitions Sake 2023