Fortresses

Discussion of anything and everything relating to chess playing software and machines.

Moderator: Ras

User avatar
Nordlandia
Posts: 2834
Joined: Fri Sep 25, 2015 9:38 pm
Location: Sortland, Norway

Fortresses

Post by Nordlandia »

[d]8/8/8/4N3/8/B1k2p1p/4Pp1P/2K5 w - - 0 0
[pgn][Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "New game"]
[Black "?"]
[Result "*"]
[SetUp "1"]
[FEN "8/8/8/4N3/8/B1k2p1p/4Pp1P/2K5 w - - 0 0"]
[PlyCount "15"]

1. Bb4+ Kb3 2. Nxf3 f1=Q+ 3. Be1 Qg2 4. Bg3 Kc3 5. Kd1 Qh1+ 6. Be1+ Kc4 7. Kd2
Qg2 8. Bg3[/pgn]
Top
Paloma
Posts: 1227
Joined: Thu Dec 25, 2008 9:07 pm
Full name: Herbert L

Re: Fortresses

Post by Paloma »

1. Bb4 Kb3 2. Nxf3 f1=Q 3. Be1 Qg2 4. Bg3 Kc3 5. Kd1 Qh1 6. Be1 Kc4 7. Kd2 Qg2 8. Bg3
after 6...Kc4 (which is wrong) why not 7.Nxd2+ and Black losing the Queen. :wink:
Top
User avatar
hgm
Posts: 28487
Joined: Fri Mar 10, 2006 10:06 am
Location: Amsterdam
Full name: H G Muller

Re: Fortresses

Post by hgm »

Unlike most fortressesm this would be one that is not easy to detect by static analysis. It does satisfy the usual primary filter condition, namely that all black's strength is in a single piece. As usual, all white's pieces protect each other, and black has no passers.

But normally it is the attacking King being cut off from the defending King that makes the position unwinnable. It is quite unusual that the Queen is trapped in a sub-section of the board, like it is here.
Top
User avatar
Nordlandia
Posts: 2834
Joined: Fri Sep 25, 2015 9:38 pm
Location: Sortland, Norway

Re: Fortresses

Post by Nordlandia »

Here is another one:

[d]4KBbn/5p2/6p1/3k1P2/3N2P1/7p/8/8 w - - 0 0

[pgn][Event "Albert van Tets | Ndaba'Skaalcpitte"]
[Site "?"]
[Date "1981.??.??"]
[Round "?"]
[White ""]
[Black ""]
[Result "*"]
[SetUp "1"]
[FEN "4KBbn/5p2/6p1/3k1P2/3N2P1/7p/8/8 w - - 0 0"]
[PlyCount "7"]

1. f6 h2 2. g5 h1=Q 3. Bh6 Kxd4 4. Kf8 *
[/pgn]

Still stockfish dev think it's ahead +10 :lol:
Top
Henk
Posts: 7251
Joined: Mon May 27, 2013 10:31 am

Re: Fortresses

Post by Henk »

Fortress ?

[d] 8/1p6/kp6/2n5/p1K1b3/P7/1Q6/8 b - - 99 104

If so then it will be too difficult for Skipper to detect it for it does not show value 0

Code: Select all

Depth  Value   Time(seconds)   Nodes
 27    0.4560      61.48    68489078   a6a7 c4d4 
 26    0.4560      38.72    42775427   a6a7 c4d4 
 25    0.4560      58.69    63111338   a6a7 c4d4 e4d3 b2g2 d3f5 g2f2 f5b1 f2e2 b1g6 d4e3 g6e4 e3f2 a7b8 f2g3 b8a7 
 24    0.4816       5.39     6241431   a6a7 b2e5 e4b1 c4d5 a7a6 e5e7 b1e4 d5c4 a6a5 c4c3 a5b5 c3d4 
 23    0.4816       3.66     3999361   a6a7 b2e5 e4b1 c4d5 a7a6 e5e7 c5e4 d5c4 a6a7 
 22    0.4816       1.95     2612797   a6a7 b2e5 e4b1 c4d5 a7a6 
 21    0.4816       1.91     1773300   a6a7 b2e5 e4b1 c4d5 a7a6 
 20    0.4816       0.96     1270216   a6a7 b2e5 e4b1 c4d5 a7a6 e5e7 c5e4 d5c4 
 19    0.4816       0.58      731089   a6a7 b2e5 e4b1 
 18    0.4816       0.66      808390   a6a7 b2e5 e4b1 
 17    0.4816       0.98      819264   a6a7 b2e5 e4b1 c4d5 c5d3 e5e7 b1a2 d5d4 
 16    0.4816       0.23      302439   a6a7 b2e5 e4d3 c4b4 a7a6 
 15    0.4816       0.16      200586   a6a7 b2e5 e4d3 c4b4 a7a6 
 14    0.4816       0.25      330944   a6a7 b2e5 e4d3 c4b4 a7a6 e5d5 d3e4 d5f7 a6a7 b4c4 
 13    0.4944       0.07       94560   a6a7 b2e5 
 12    0.4944       0.05       62769   a6a7 b2e5 
 11    0.4944       0.04       48948   a6a7 b2e5 e4d3 c4d5 a7a6 e5e7 c5e4 
 10    0.5328       0.01       12496   a6a7 b2g7 c5d3 
  9    0.5328       0.00        5970   a6a7 b2g7 c5d3 c4c3 a7a6 
  8    0.5328       0.00        2289   a6a7 b2g7 
  7    0.5328       0.00        1380   a6a7 b2g7 
  6    0.5328       0.00        1262   a6a7 
  5    0.5328       0.00         440   a6a7 
  4    0.5328       0.00        3245   a6a7 b2g7 c5d3 c4c3 
  3    0.5328       0.00        1707   e4d3 c4d5 c5e4 
  2    0.5328       0.00        1956   e4d3 c4d5 c5e4 
  1    0.5712       0.00          79   c5d3
Top
User avatar
Nordlandia
Posts: 2834
Joined: Fri Sep 25, 2015 9:38 pm
Location: Sortland, Norway

Re: Fortresses

Post by Nordlandia »

Forced mate in 13!

[d]6bn/p4p1k/rp3Pp1/rp2BBP1/1p6/pK6/P2P4/8 w - - 0 0
Top
User avatar
Nordlandia
Posts: 2834
Joined: Fri Sep 25, 2015 9:38 pm
Location: Sortland, Norway

Re: Fortresses

Post by Nordlandia »

Josef Hasek, Sach | 1965

[d]8/1p1q1k2/1Pp5/p1Pp4/P2Pp1p1/4PpPp/1N3P1P/3B1K2 w - - 0 0

[pgn][Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "New game"]
[Black "?"]
[Result "*"]
[SetUp "1"]
[FEN "8/1p1q1k2/1Pp5/p1Pp4/P2Pp1p1/4PpPp/1N3P1P/3B1K2 w - - 0 0"]
[PlyCount "7"]

1. Bb3 Qc8 2. Nd1 Qa8 3. Bc4 dxc4 4. Nc3 *[/pgn]
Top
fishpov
Posts: 114
Joined: Sat Mar 07, 2015 6:05 pm

Re: Fortresses

Post by fishpov »

1.Bb3 Qc8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 ! seems also good
Top
Vinvin
Posts: 5325
Joined: Thu Mar 09, 2006 9:40 am
Full name: Vincent Lejeune

Re: Fortresses

Post by Vinvin »

Nordlandia wrote:[d]8/8/8/4N3/8/B1k2p1p/4Pp1P/2K5 w - - 0 0

1. Bb4+ Kb3 2. Nxf3 f1=Q+ 3. Be1 Qg2 4. Bg3 Kc3 5. Kd1 Qh1+ 6. Be1+ Kc4 7. Kd2
Qg2 8. Bg3
Bb4 is found immediately (depth 2) by Stockfish.
Because other moves are clearly losing.
Top
Vinvin
Posts: 5325
Joined: Thu Mar 09, 2006 9:40 am
Full name: Vincent Lejeune

Re: Fortresses

Post by Vinvin »

Nordlandia wrote:Josef Hasek, Sach | 1965

[d]8/1p1q1k2/1Pp5/p1Pp4/P2Pp1p1/4PpPp/1N3P1P/3B1K2 w - - 0 0

1. Bb3 Qc8 2. Nd1 Qa8 3. Bc4 dxc4 4. Nc3
A couple of seconds for Stockfish :

Code: Select all

Stockfish_16033114_x64_modern:
...
 38/40	00:01	 14 157k	13 772k	-6,21	1.Bc2 Qc8 2.Ke1 Qa8 3.Nd3 exd3 4.Bxd3 Kf6 5.Kd2 Qe8 6.Kc3 Qd7 7.Kd2 Qd8 8.Kc2 Kg5 9.Kc3 Qd7 10.Kc2 Qe7 11.Kc3 Kf6 12.Kc2 Qf7 13.Kc3 Kg5 14.Kc2 Qe8 15.Kd2 Qe6 16.Kc3 Qg8 17.Kc2 Qa8 18.Kc3 Qd8 19.Kd2 Qf6 20.Ke1 Qf8
 39/44	00:03	 52 775k	14 519k	-6,34	1.Bb3 Qd8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 Ke6 6.Kc3 Kd5 7.Kb2 Qa8 8.Kc3 Ke6 9.Bxc4+ Kf5 10.Bb3 Qd8 11.Bc4 Qe7 12.Ba2 Qf6 13.Bb3 Kg6 14.Kd2 Kg5 15.Kc3 Kf5 16.Bc4 Qd8 17.Bf7 Qg5 18.Bb3 Qg6 19.Bc4 Qe8 20.Bb3 Kg5 21.Ba2 Qd7 22.Bc4 Qf5
 40/45	00:03	 53 856k	14 516k	-6,34	1.Bb3 Qd8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 Ke6 6.Kc3 Kd5 7.Kb2 Qa8 8.Kc3 Ke6 9.Bxc4+ Kf5 10.Bb3 Qd8 11.Bc4 Qe7 12.Ba2 Qf6 13.Bb3 Kg6 14.Kd2 Kg5 15.Kc3 Kf5 16.Bc4 Qd8 17.Bf7 Qg5 18.Bb3 Qg6 19.Bc4 Qe8 20.Bb3 Kg5 21.Ba2 Qd7 22.Bc4 Qf5 23.Kd2
 41/46	00:04	 66 187k	14 620k	-6,34	1.Bb3 Qd8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 Ke6 6.Kc3 Kd5 7.Kb2 Qa8 8.Kc3 Ke6 9.Bxc4+ Kf5 10.Bb3 Qd8 11.Bc4 Qe7 12.Ba2 Qf6 13.Bb3 Kg6 14.Kd2 Kg5 15.Kc3 Kf5 16.Bc4 Qd8 17.Bf7 Qg5 18.Bb3 Qg6 19.Bc4 Qe8 20.Bb3 Kg5 21.Ba2 Qd7 22.Bc4 Qf5 23.Kd2 Qf6
 42/47	00:04	 68 373k	14 610k	-6,34	1.Bb3 Qd8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 Ke6 6.Kc3 Kd5 7.Kb2 Qa8 8.Kc3 Ke6 9.Bxc4+ Kf5 10.Bb3 Qd8 11.Bc4 Qe7 12.Ba2 Qf6 13.Bb3 Kg6 14.Kd2 Kg5 15.Kc3 Kf5 16.Bc4 Qd8 17.Bf7 Qg5 18.Bb3 Qg6 19.Bc4 Qe8 20.Bb3 Kg5 21.Ba2 Qd7 22.Bc4 Qf5 23.Kd2 Qf6 24.Kc3
 43/48	00:04	 71 733k	14 610k	-6,34	1.Bb3 Qd8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 Ke6 6.Kc3 Kd5 7.Kb2 Qa8 8.Kc3 Ke6 9.Bxc4+ Kf5 10.Bb3 Qd8 11.Bc4 Qe7 12.Ba2 Qf6 13.Bb3 Kg6 14.Kd2 Kg5 15.Kc3 Kf5 16.Bc4 Qd8 17.Bf7 Qg5 18.Bb3 Qg6 19.Bc4 Qe8 20.Bb3 Kg5 21.Ba2 Qd7 22.Bc4 Qf5 23.Kd2 Qg6 24.Bb3 Qe8
 44/49	00:05	 80 669k	14 640k	-6,34	1.Bb3 Qd8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 Ke6 6.Kc3 Kd5 7.Kb2 Qa8 8.Kc3 Ke6 9.Bxc4+ Kf5 10.Bb3 Qd8 11.Bc4 Qe7 12.Ba2 Qf6 13.Bb3 Kg6 14.Kd2 Kg5 15.Kc3 Kf5 16.Bc4 Qd8 17.Bf7 Qg5 18.Bb3 Qg6 19.Bc4 Qe8 20.Bb3 Kg5 21.Ba2 Qd7 22.Bc4 Qf5 23.Kd2 Qg6 24.Bb3 Qe8 25.Kc3
 45/50	00:07	 110 008k	14 546k	-6,34	1.Bb3 Qd8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 Ke6 6.Kc3 Kd5 7.Kb2 Qa8 8.Kc3 Ke6 9.Bxc4+ Kf5 10.Bb3 Qd8 11.Bc4 Qe7 12.Ba2 Qf6 13.Bb3 Kg6 14.Kd2 Kg5 15.Kc3 Kf5 16.Bc4 Qd8 17.Bf7 Qg5 18.Bb3 Qg6 19.Bc4 Qe8 20.Bb3 Kg5 21.Ba2 Qd7 22.Bc4 Qf5 23.Kd2 Qg6 24.Bb3 Qe8 25.Kc3 Qe7
 46/51	00:08	 121 815k	14 514k	-6,34	1.Bb3 Qd8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 Ke6 6.Kc3 Kd5 7.Kb2 Qa8 8.Kc3 Ke6 9.Bxc4+ Kf5 10.Bb3 Qd8 11.Bc4 Qe7 12.Ba2 Qf6 13.Bb3 Kg6 14.Kd2 Kg5 15.Kc3 Kf5 16.Bc4 Qd8 17.Bf7 Qg5 18.Bb3 Qg6 19.Bc4 Qe8 20.Bb3 Kg5 21.Ba2 Qd7 22.Bc4 Qf5 23.Kd2 Qg6 24.Bb3 Qe8 25.Kc3 Qe7 26.Bc2
 47/52	00:09	 133 064k	14 478k	-6,34	1.Bb3 Qd8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 Ke6 6.Kc3 Kd5 7.Kb2 Qa8 8.Kc3 Ke6 9.Bxc4+ Kf5 10.Bb3 Qd8 11.Bc4 Qe7 12.Ba2 Qf6 13.Bb3 Kg6 14.Kd2 Kg5 15.Kc3 Kf5 16.Bc4 Qd8 17.Bf7 Qg5 18.Bb3 Qg6 19.Bc4 Qe8 20.Bb3 Kg5 21.Ba2 Qd7 22.Bc4 Qf5 23.Kd2 Qg6 24.Bb3 Qe8 25.Kc3 Qe7 26.Bc2 Kf5
 48/53	00:10	 156 887k	14 477k	-6,34	1.Bb3 Qd8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 Ke6 6.Kc3 Kd5 7.Kb2 Qa8 8.Kc3 Ke6 9.Bxc4+ Kf5 10.Bb3 Qd8 11.Bc4 Qe7 12.Ba2 Qf6 13.Bb3 Kg6 14.Kd2 Kg5 15.Kc3 Kf5 16.Bc4 Qd8 17.Bf7 Qg5 18.Bb3 Qg6 19.Bc4 Qe8 20.Bb3 Kg5 21.Ba2 Qd7 22.Bc4 Qf5 23.Kd2 Qg6 24.Bb3 Qe8 25.Kc3 Qe7 26.Ba2 Qf6 27.Bc4
 49/54	00:12	 180 283k	14 331k	-6,34	1.Bb3 Qd8 2.Ke1 Qa8 3.Kd2 Qa6 4.Nc4 dxc4 5.Ba2 Ke6 6.Kc3 Kd5 7.Kb2 Qa8 8.Kc3 Ke6 9.Bxc4+ Kf5 10.Bb3 Qd8 11.Bc4 Qe7 12.Ba2 Qf6 13.Bb3 Kg6 14.Kd2 Kg5 15.Kc3 Kf5 16.Bc4 Qd8 17.Bf7 Qg5 18.Bb3 Qg6 19.Bc4 Qe8 20.Bb3 Kg5 21.Ba2 Qd7 22.Bc4 Qf5 23.Kd2 Qg6 24.Bb3 Qe8 25.Kc3 Qe7 26.Ba2 Qf6 27.Bc4 Kg6
Top

Return to “Computer Chess Club: General Topics”