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MatPlus.Net Forum General Still another free for all construction task
 
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(21) Posted by Michal Dragoun [Saturday, Aug 10, 2013 23:16]

I don´t know the intention, but if Black doesn´t help, he can give after promotion (e. g. 1.Kg2 Rg8+ 2.Kh3 f1Q+ or 1.Be4 Rh1+ 2.Kg2 f1Q+) quickly mate (or - if he don´t want to do so - perpetual check).
 
   
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(22) Posted by Geir Sune Tallaksen Østmoe [Sunday, Aug 11, 2013 00:26]

The goal is for White to "restart" the 50-move rule, which Black tries to prevent. Thus, when either player makes a capture or a pawn move (such as promotion), the goal is fulfilled.
 
   
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(23) Posted by Michal Dragoun [Sunday, Aug 11, 2013 01:03]

Ah, sorry! For the next time I should read the whole thread more carefully.
 
   
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(24) Posted by Arno Tungler [Sunday, Aug 11, 2013 11:38]

Very nice! However, again I think that this can be shortened… (Probably I made another stupid mistake as the last time above, excuse me, please!)
As I see it, White starts with 1.Kg2! Rg8+ 2.Kh3 Rh8+ … 6.Kh7 Rg1! 7.Be4! Rh1+ … 13.Kh2 Rg8! 14.Bd3! Rh8+ … 20.Kh7 Rg1 21.Bf1! Rh1+ 22.Bh3 Ba2 23.Kg6! Rg1+ and now I would play 24.Bg2! 28.Kh2 29.Bh3!
What now to do for Black? If 29… Rg8 follows 30.Bg4! Rh8+ 31.Bh5! 32.Kg2 and Black must avoid Rg8+? because of 33.Bg6! 36.Kh5 Rh8+ 37.Bh7! 39.Kg7 Rf8 and the wB runs without hindrance to 49.Bxb1
So, better is 29….Bb1 30.Bg4 Ba2 31.Bh5 Ba2 32.Be8 Bb1! (after Rg8? Again 33.Bg6! etc.) 33.Bd7 Rg8 34.Bc8 Rh8+ … 44.Kh7 Rg1 45.Ba6 Rh1+ … 51.Kh2 Rg8 52.Bb5 Rh8+ … 58.Kh7 Rg1 59.Ba4 Rh1+ … 65.Kh2 Rg8 66.Bb3 Rh8+ … 72.Kh7 Rg1 73.Ba2 Rh1+ … 79.Kh2 and 80. restart.
What did I overlook??
 
   
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(25) Posted by Arno Tungler [Sunday, Aug 11, 2013 12:01]; edited by Arno Tungler [13-08-11]

(= 9+9 )


Am I right that this gives a restart in 103 moves??

EDIT: No, it does not, as the wK can be fixed on g6 and g4 before the wB has escaped. So, we need to return to the wPf4 (without bPe5) and that gives only 97 moves, if I count right...

I have changed the diagram accordingly.
 
   
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(26) Posted by Hauke Reddmann [Sunday, Aug 11, 2013 16:52]

I intended h-restart, but feel free to try out direct or even
self-restart :-) (It's more interesting from the strategic
viewpoint, anyway.)

Hauke
 
   
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(27) Posted by Geir Sune Tallaksen Østmoe [Sunday, Aug 11, 2013 20:46]; edited by Geir Sune Tallaksen Østmoe [13-08-11]

Nice work! Yes, I think you are right that the new position is 97 moves. 100 feels very close now...

In my position, I still think 93 moves is correct, but apparently we both missed something this time! I missed the fact that with Bh7/Rh8, White can annoy Black with Kg7. However, after 39.Kg7, Black gets the rook back into play with 39...Rd8! 40.Bg6 Rd1 41.Be8 Rg1+ etc. which happens to be three moves longer than my main line.

My line goes 24.Bg4 Bb1 25.Kh8 Rh1+ 26.Bh5 Ba2 27.Kg7 Rg1+ 28.Bg6 Bb1 29.Kh8 Rh1+ 30.Bh7 Ba2 31.Kg7 Bb1 32.Bg8 Rg1+ ... 39.Kh2 Rg7 40.Bf7 Rh7+ ... 45.Kg6 Rh1 46.Be8 ... 93.Bxb1.

Edit: But now I see that White can improve with 40.Kh3!! and Black is in zugzwang! 40...Rg1 41.Bf7 Rh1+ 42.Kg2 Rg1+ 43.Kh2 Rg7 44.Be8 and if I am counting right, White has saved one(!) move. If this is correct, then 92 moves is the correct stipulation.
 
   
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(28) Posted by Geir Sune Tallaksen Østmoe [Sunday, Aug 11, 2013 22:22]

Hauke: How does self-restart work? White forces Black to make the restart? In the "direct" ones by Arno and me, it doesn't matter which player makes the restart.
 
   
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(29) Posted by Geir Sune Tallaksen Østmoe [Sunday, Aug 11, 2013 23:24]

Bad news, Arno. I think your position is only 92 moves. I first agreed on 97 moves based on the following:

1.Kg6 Rd1 2.Kh5! ... 6.Kh2 Rg7 7.Bh7 Ba2 8.Bg6 Bb1 9.Bh5 Rh7 10.Kg2 Rg7+ 11.Bg4 Ba2 12.Kh2 Rh7+ 13.Bh3 Bb1 14.Kg3 Rg7+ ... 19.Kh6 Rg1 20.Bf1 Rh1+ ... 97.Bxb1. But here White has 20.Bg2!! when Black has no waiting move. I see nothing better than 20...Ba2 21.Bf1 Bb1 22.Bd3 ... 92.Bxb1.

Annoyingly, it seems impossible in the current setting to add a Black piece that can make tempo moves. A knight could make tempo moves between a8/b6, and a pawn on b2 would prevent it from entering the kingside, but not only would the position become illegal, it would also not solve the problem - Black could put the knight on a4 and reply to 14.Kg3 by 14...Ne2+! 15.Kg4 Nac3!

I have one suggestion which I think keeps the position correct and improves the solution by one move: Move the f2-pawn to b4.

(= 9+9 )


Correct me if I'm wrong, but I don't see any way for Black to exploit the increased mobility of the Bc5, except for adding one move to the solution by 6...Bg1+ 7.Kh3 Bc5. Using the 21.Bg2! Ba2 22.Bf1 trick, this leads to a restart in 93 moves. With the f2 pawn gone, White could try to play Kf1-e1 while the bishop is still on the kingside, but because of the b4-pawn, Black's queenside defends itself, so I don't think White can use that for anything.
 
   
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(30) Posted by Arno Tungler [Monday, Aug 12, 2013 04:08]

Very good analyzed, as awaited I overlooked the main things... I really like the "Rundlauf" in your 93-mover and the nice additional idea with Bg1+! Unfortunately, There is no time now to have a deeper look to that but you are right that 100 should be possible...

Just one quick question: Could we not add a tempo-winner by adding a bS (or bP) on c5? See the follwoing diagram, maybe back to 97?
Seemingly, the "free" bB cannot make harm as it is in a huge cage.

(= 9+10 )

 
   
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(31) Posted by Hauke Reddmann [Monday, Aug 12, 2013 10:56]

@Geir: I would have it this way:
h - both White and Black want to restart
d - White wants to restart, Black tries to hinder him from
all captures and pawn moves
You're right: since "restart" is a symmetric goal, s=d under
color switch.
This symmetry can only be resolved by changing the goal from
"restart" to "White pawn move" or "White capture" (or both,
or any asymmetric combination of W&B move types).

Hauke
 
   
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(32) Posted by Jacques Rotenberg [Monday, Aug 12, 2013 12:57]

You may give a specific s stipulation :

white will not restart itself : black has to be forced to make a restart- move
 
   
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(33) Posted by seetharaman kalyan [Monday, Aug 12, 2013 20:24]

All this is fine. If the intention is to beat the 50-move rule, with or without help, how can the solutions be more than 50 moves?
 
   
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(34) Posted by Jacques Rotenberg [Monday, Aug 12, 2013 20:42]

Why not ?
 
   
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(35) Posted by Geir Sune Tallaksen Østmoe [Wednesday, Aug 14, 2013 21:24]

I was about to give up (for now) on this, when I suddenly hit on another idea:

(= 13+12 )


Could this really be a restart in exactly(!) 100 moves?
 
   
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(36) Posted by Arno Tungler [Thursday, Aug 15, 2013 16:57]; edited by Arno Tungler [13-08-15]

Yes, that seems true. Congratulations, a nice pendulum of black rook and knight and a surprising "endgame" after move 96!
 
   
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(37) Posted by Sven Hendrik Lossin [Thursday, Aug 15, 2013 20:48]

I am still a bit confused about that. I think I understood the stipulation but black can avoid the restart in the last example by mating the white king. Or does that also count as "restart"?
 
   
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(38) Posted by Geir Sune Tallaksen Østmoe [Thursday, Aug 15, 2013 21:24]

I agree that a checkmate does not count as a restart, but unless I have missed something, Black has no way to give mate without allowing a restart first. Black is threatening 1...Qb6+ with mate to follow, so 1.Kc8 is forced. Now, however, Black's queen cannot move since White would restart with 2.a5.
 
   
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(39) Posted by Sven Hendrik Lossin [Thursday, Aug 15, 2013 22:22]

Okay, you are right. Well done!
 
   
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(40) Posted by Hauke Reddmann [Friday, Aug 16, 2013 11:00]; edited by Hauke Reddmann [13-08-16]

Geir, could you go into details?
The point, as I see it, is that White getting checkmated foils
the restart, so he can NOT hide on h6 and must constantly
molest the rook to win the time to play his rook over to b3.

EDIT: And no, c6 is no way to mate White, stupid me :-)

Hauke
 
   
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