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(Message started by: The_Jeh on Aug 18th, 2007, 5:12pm)
Title: Double-goal
Post by The_Jeh on Aug 18th, 2007, 5:12pm
What happens if on the same turn both rabbits reach the goal? I suppose it is a draw. I realize this could only happen as a result of extreme stupidity, but is the server prepared to handle such an occurrence?
Title: Re: Double-goal
Post by jdb on Aug 18th, 2007, 6:02pm
On a double goal, the side that made the move wins.
Title: Re: Double-goal
Post by aaaa on Aug 19th, 2007, 4:44pm
What about if the last two opposing rabbits "get it" in one move under tournament rules?
Title: Re: Double-goal
Post by Anar on Aug 19th, 2007, 5:21pm
I think it goes something like that:

If after a single turn should arise a situation which would cause both playing sides to win/lose, the moving side wins.
Title: Re: Double-goal
Post by The_Jeh on Aug 19th, 2007, 5:34pm

on 08/18/07 at 18:02:15, jdb wrote:
On a double goal, the side that made the move wins.


But is that because Omar wants it that way, or because the server checks the player that moved first and then doesn't bother checking the other player if the first player goaled? I can't find any clause that governs this situation. Actually, here is the fourth "special situations" rule:

A player may push or pull the opponent's rabbit into the goal. If at the end of the turn the rabbit remains there, the player loses. However if the rabbit is moved back out of the goal row before the end of the turn, the player does not lose.

Strictly interpreted, this gives the victory to the side that *didn't* move unless a clause is added regarding double-goals.

And I don't think a player should get more than 1 point in a match for goaling two rabbits. The reason is that if the game continued after a rabbit is goaled, other rabbits might be able to goal, too. It is a coincidence and a novelty that two rabbits might be goaled on the same turn, and not the result of a game-long strategy.
Title: Re: Double-goal
Post by Fritzlein on Aug 19th, 2007, 6:53pm

on 08/19/07 at 17:21:54, Anar wrote:
If after a single turn should arise a situation which would cause both playing sides to win/lose, the moving side wins.

I haven't heard it stated so succinctly, but that seems to be the way Omar has ruled on ambiguities so far.  For example, in tournaments you lose the game for losing all your rabbits, but if you capture the last opposing rabbit in the same turn you lose your last rabbit, you win.


on 12/11/05 at 10:58:41, omar wrote:
So if after my move is over, all of the opponents rabbits have been captured then I win. Thus, the player making the move which leads to the otherwise drawn position wins. In general I perfer not to have to disect the move to determine the result. The win/lose conditions don't need to be applied at the step level, but rather only at the move level.

I like Anar's statement because it covers case that Omar has not yet explicitly ruled on.  For example, what if I take your last rabbit, immobilizing myself in the process?  This would be clear, because the side moving caused both players to meet a victory condition, so the side moving would win.

BUT what if I immobilize my opponent in the same turn as I push his rabbit to goal?  Then I have caused each of us to meet a victory condition, so Anar's unambiguous rule states that I win, but somehow my intuition wants goals to be more primary than mobility.  Hmmm...

Still, I like clarity and simplicity more than I like the primacy of goals.  Thus I would like there to be three victory conditions plus a simple tiebreaker:

1. You have a rabbit on the goal line
2. Your opponent has no rabbits
3. Your opponent can't move on his turn

If both players meet a victory condition between two turns, then the player who moved last wins.

This is so much simpler than rule case-by-case.  What do you think, Omar?

I'm not sure what Omar would want to rule when draws are allowed.  What if the draw condition (no rabbits) is met at the same time as one player is immobilized?  Does the draw or win take priority?  But really I don't care too much, because I want the no-rabbits draw to be eliminated for all games.
Title: Re: Double-goal
Post by Fritzlein on Aug 19th, 2007, 6:58pm

on 08/19/07 at 17:34:20, The_Jeh wrote:
And I don't think a player should get more than 1 point in a match for goaling two rabbits.

Certainly not.  That sort of rule would encourage the winning side to prolong the game, trying to get two (or four!) rabbits to goal on the same move.
Title: Re: Double-goal
Post by The_Jeh on Aug 19th, 2007, 11:47pm

on 08/19/07 at 18:53:35, Fritzlein wrote:
BUT what if I immobilize my opponent in the same turn as I push his rabbit to goal?  Then I have caused each of us to meet a victory condition, so Anar's unambiguous rule states that I win, but somehow my intuition wants goals to be more primary than mobility.  Hmmm...


No, you don't win, because rabbit goal ought to be checked at the end of the turn, while immobilizations ought to be checked at the point when they are pertinent, i.e. at the beginning of a player's move on that player. Thus, your opponent wins before you do.

That is how I would rule if it were my decision. Rabbits would be checked simultaneously at the end of turns, and immobilizations would be checked at the beginning of turns only on the player whose turn it is to move.

Under this system, two immobilizations cannot happen at the same time. That is good, because even if I leave myself in an immobile position at the end of my turn, perhaps by zugzwang my opponent releases me so that I can move when I need to, at the beginning of my next turn. If both players have a claim to victory at the end of a turn, I would rule it a draw.

So, it's not a matter of primacy, but of order. I don't believe in "between" turns, but rather the end of turns and the beginning of turns. Sorry to play the devil's advocate, Fritzlein.
Title: Re: Double-goal
Post by Fritzlein on Aug 20th, 2007, 7:16am

on 08/19/07 at 23:47:43, The_Jeh wrote:
Sorry to play the devil's advocate, Fritzlein.

Not at all.  It makes perfect sense the way you present it, although to my mind it is a little less simple to state the rules.  Probably Omar is with you in wanting to distinguish the end of one turn from the start of the next, if only because that's how the game server does it at present.
Title: Re: Double-goal
Post by UruramTururam on Aug 20th, 2007, 8:18am
And I wonder if there is a possible position where the onlyfinnishing move requires pulling or pushing an opposing rabbit to the goal - but I can't imagine any.
Title: Re: Double-goal
Post by The_Jeh on Aug 20th, 2007, 8:27am

on 08/20/07 at 07:16:33, Fritzlein wrote:
It makes perfect sense the way you present it, although to my mind it is a little less simple to state the rules.


Well, I just did it in roughly two or three sentences.  :)


on 08/20/07 at 08:18:14, UruramTururam wrote:
And I wonder if there is a possible position where the onlyfinnishing move requires pulling or pushing an opposing rabbit to the goal - but I can't imagine any.


It is possible. With silver to move:

Cr
RHD
eHd
Rd
xxxxxxxx

Assume silver has no pieces not shown. Although gold's rabbit is frozen right now, silver has no choice but to push the rabbit onto the goal line (xxxxxxxx) on his move. I doubt this sort of situation will ever happen.
Title: Re: Double-goal
Post by RonWeasley on Aug 20th, 2007, 9:17am
I tried double goal in game 13867.  The server worked as expected.  Testing the immobilization cases would be harder, but there are lots of creative muggles here.

I think naveed once forced the bot opponent to push his rabbit to goal.  I don't know the game number.
Title: Re: Double-goal
Post by UruramTururam on Aug 20th, 2007, 4:42pm

on 08/20/07 at 08:27:01, The_Jeh wrote:
It is possible. With silver to move:

Cr
RHD
eHd
Rd
xxxxxxxx


No, I meant the only finishing move (leading to a double goal), and not not the only possible move... See also: http://arimaa.com/arimaa/puzzles/show.cgi?p=p24
Title: Re: Double-goal
Post by The_Jeh on Aug 20th, 2007, 5:13pm
Oh, I'm sorry. No, that's impossible. Because the board is eight spaces long, but only four steps are allowed per turn, and because pieces only affect their immediate surroundings as far as freezing, what is going on at one end cannot govern a goal on the other.
Title: Re: Double-goal
Post by UruramTururam on Aug 21st, 2007, 2:23am
Yep, you're right. So assuming correct play double goal is impossible. But of course people (and bots!) do not always play correctly.  ;D

Btw. if so - a double goal is always a result of an error thus the player on move should lose, not win...
Title: Re: Double-goal
Post by Jan Kruschak on Aug 30th, 2007, 1:45am
Re: UruramTururam,

No. A double-goal shows that a single-goal must have been achieved, thus for the player who forced a double-goal it should be a "win" rather than a "loss" for that game.
Title: Re: Double-goal
Post by UruramTururam on Aug 30th, 2007, 1:54am
The goal has been achieved for both sides... I can see absolutely no reason why the active player should win (other than "the rules say so").
Title: Re: Double-goal
Post by 722caasi on Sep 10th, 2007, 4:57pm
What happens when one side goals and immobilizes the opponent?
Title: Re: Double-goal
Post by The_Jeh on Sep 10th, 2007, 5:36pm
That side wins, of course. However, I will keep preaching that they win by goal at the end of the turn, at which point the game immediately ends. So, the immobilization that would have occurred at the beginning of the next turn never actually occurs. At least, that is my contention.
Title: Re: Double-goal
Post by 722caasi on Sep 10th, 2007, 6:01pm
And what if you push a rabbit to the opponent's goal and thereby immobilize him?
like in
1w Ee5
1b re2 cd2
2w Ee5s Ee4s re2s Ee3s
(here it makes a difference)
Title: Re: Double-goal
Post by chessandgo on Sep 10th, 2007, 6:10pm
nice one, 722caasi. Gold could win by pushing the rabbit sideways, though, so adding another silver piece on f2 would make the example even more convincing.
Title: Re: Double-goal
Post by aaaa on Sep 10th, 2007, 6:54pm

on 09/10/07 at 16:57:55, 722caasi wrote:
What happens when one side goals and immobilizes the opponent?

See for yourself. (http://arimaa.com/arimaa/gameroom/comments.cgi?gid=42733)
Title: Re: Double-goal
Post by 722caasi on Sep 10th, 2007, 7:46pm

on 09/10/07 at 18:10:15, chessandgo wrote:
nice one, 722caasi. Gold could win by pushing the rabbit sideways, though, so adding another silver piece on f2 would make the example even more convincing.

Alright, lets do  
1w Ee5
1b re2 cd2 mf2
2w Ee5s Ee4s re2s Ee3s
Title: Re: Double-goal
Post by RonWeasley on Sep 11th, 2007, 8:04am
Goals are checked at end of turn.  Goal for the mover is checked first.  So in this case, at the end of gold's turn, a silver rabbit has reached goal and silver wins.

If the goal had not been achieved, then silver's move begins with an immobilization check, which would register a win for gold.

If there were a no-rabbit win rule, a move prior to this position would have given silver a win at the end of the move where gold's last rabbit was removed.

So a turn sequence looks like:

Check immobilization.
Check no rabbit draw.
Enter and implement move.
Check mover goal.
(Check non-mover no rabbits.)
Check repitition (3).
Check non-mover goal.
(Check mover no rabbits)

Did I remember everything?
Title: Re: Double-goal
Post by 722caasi on Sep 11th, 2007, 8:51am

on 09/11/07 at 08:04:38, RonWeasley wrote:
Did I remember everything?

I think you forgot draw by score and timeout, but thats it!


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