Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Want really hard positions? Here's 10 pieces

Author: Bernhard Bauer

Date: 00:02:11 11/05/99

Go up one level in this thread


On November 03, 1999 at 19:11:21, Howard Exner wrote:

>On November 03, 1999 at 16:35:22, Dann Corbit wrote:
>
>>On November 03, 1999 at 15:53:29, Howard Exner wrote:
>>
>>>On November 03, 1999 at 13:07:48, Dann Corbit wrote:
>>>
>>>>Here is analysis at fairly long time control.  I think most of the suggested
>>>>moves are actually bugs in the epd test suite.
>>>
>>>Just one of them is wrong. That's the one that suggests Rxh2. The rest are fine,
>>>just difficult for computers. Cross reference your analysis with the one I
>>>posted or just enter in the moves from my post and then see if your program
>>>agrees or not. Maybe you'll find something that was missed by the ECM98 project.
>>Is this the correct projection from your analysis?:
>>
>>r4k1r/pp2pp2/3p1b2/q2PnQpp/3N4/1BP3P1/PP3PP1/3RR1K1 w - - bm Rxe5; id
>>"ECM.1291"; c0 "Unknown -- possibly suspect";
>
>1. Rxe5 dxe5 2. d6 Qd8 3. dxe7+ Qxe7 4. Nf3
>This one I'm not as sure as the others. Maybe there is some better defense for
>black?
>
>>2b1rr1k/1p5p/1Ppp2q1/p3bN2/2P1n3/5R2/PBQ3BP/3R2K1 w - - bm Nxd6;id "ECM.1061";
>>pv Nxd6 Rxf3 Nxe8 Bxb2 Qxb2+ Kg8 Rd8 Rf8 Rxc8 Rxe8 Rxe8+ Qxe8 Qe2 Qd8 Bxe4;
>>r4rk1/ppp3b1/3p1qp1/3Pp3/2P1Bn2/4BP2/PP1Q4/2K3RR w - - bm Rxg6; id "ECM.1149";
>>pv Rxg6 Nxg6 Bg5 Qf7 Qh2 Rfe8 Qh7+ Kf8 Bxg6 Qg8 Qh3 Re7 Bxe7+ Kxe7 Qh4+;
>>rq3r1k/p2n1p2/1pbb1np1/2p2BB1/8/2N2N2/PP3QPP/3R1RK1 w - - bm Rxd6; id
>>"ECM.1169"; pv Rxd6 Qxd6 Rd1 Qb8 Bxd7 Nxd7 Qh4+ Kg8 Rxd7 Bxf3 Nd5 Qe5 Nf6+;
>>1r3rk1/6p1/p1pb1qPp/3p4/4nPR1/2N4Q/PPP4P/2K1BR2 b - - bm Rxb2; id "ECM.1229"; pv
>>Rxb2 Kxb2 Ba3+ Kxa3 Rb8;
>>rnb2rk1/pp2bppp/2p5/q7/4NN2/4B1QP/PPP3P1/2KR3R w - - bm Rd5; id "ECM.1259"; pv
>>Rd5 cxd5 Nh5 Bg4 Qxg4 g6 Nhf6+ Bxf6 Nxf6+ Kh8 Qh4;
>>r1b5/p2k1r1p/3P2pP/1ppR4/2P2p2/2P5/P1B4P/4R1K1 w - - bm Bxg6; id "ECM.1545"; pv
>>Bxg6 hxg6 Re7+ Rxe7 dxe7+ Kxe7 Rd8;
>>r4rk1/ppq3pp/2p1Pn2/4p1Q1/8/2N5/PP4PP/2KR1R2 w - - bm Rxf6; id "ECM.1574"; pv
>>Rxf6 Rxf6 Rd7 Rg6 Qe7 Qc8 Qf7+ Kh8 e7 Qg8 Qxg8+ Rxg8 Ne4;
>>r2q3r/2pkb1p1/p2p1n2/4p1p1/Pp2P1P1/1QP5/1P1P2PP/RNB2RK1 b - - bm Rxh2; id
>>"ECM.1621";
>
>The book line showed some faulty lines here for white. I recall that Amir Ban
>showed that Rxh2 leads nowhere and the participants of the ECM98 project
>concurred. There is lengthy analysis of these and many other positions in past
>CCC posts( mostly titled ECM98 Errata).
>
>>2rq1rk1/pp1bnpbp/4p1p1/3pP1N1/3P2Q1/2PB4/P4PPP/R1B1R1K1 w - - bm Nxh7; id
>>"ECM.1622"; pv Nxh7 Kxh7 Qh4+ Kg8 Bg5 Re8 Re3 Rxc3 Rh3 Kf8 Qh7;
>
>The above positions looks accurate.

Just for comparison I ran those 10 positions with crafty and got:

PFGA: EPD record: 1   ID: ECM.1061
               15->  24:36   2.10   1. Bxe5+ dxe5 2. Nh4 Qh5 3. Qxe4 Rg8
                                    4. Nf5 Rg4 5. Qc2 Bxf5 6. Rxf5 Rxc4
                                    7. Rxh5 Rxc2 8. Be4 Re2 9. Rxh7+ Kg8
                                    10. Bg6 Re6
               16    41:39   2.12   1. Bxe5+ dxe5 2. Nh4 Qh5 3. Qxe4 Rg8
                                    4. Nf5 Rg4 5. Qc2 Qg6 6. Rd6 Qf7 7.
                                    c5 Rc4 8. Qf2 Rc1+ 9. Bf1 Qc4 10. Kg2
                                    Qxc5
               16->  62:17   2.12   1. Bxe5+ dxe5 2. Nh4 Qh5 3. Qxe4 Rg8
                                    4. Nf5 Rg4 5. Qc2 Qg6 6. Rd6 Qf7 7.
                                    c5 Rc4 8. Qf2 Rc1+ 9. Bf1 Qc4 10. Kg2
                                    Qxc5
              time=90:00  cpu=200%  mat=-1  n=2697156624  fh=0%  nps=499458
              ext-> checks=161338095 recaps=9336412 pawns=1740463 1rep=10915623
thrt:666055
              predicted=0  nodes=2697156624  evals=454494969
              endgame tablebase-> probes done=0  successful=0
              SMP->  split=2103  stop=342  data=9/64  cpu=180:14  elap=90:00

PFGA: EPD record: 2   ID: ECM.1149
               15->  10:52   1.90   1. Rg4 g5 2. Bxf4 exf4 3. Rh5 Qd4 4.
                                    Qxd4 Bxd4 5. Rgxg5+ Kf7 6. Rh7+ Ke8
                                    7. Rxc7 Rb8 8. Rg6 Kd8 9. Rh7 Be3+
                                    10. Kc2 Bc5
               16    21:24   1.75   1. Rg4 g5 2. Bxf4 exf4 3. Qg2 Bh6 4.
                                    Rgh4 Bg7 5. Rh5 Qd4 6. Rxg5 Rf7 7.
                                    Kb1 Kf8 8. Qe2 Bf6 9. Rg4
               16->  36:31   1.75   1. Rg4 g5 2. Bxf4 exf4 3. Qg2 Bh6 4.
                                    Rgh4 Bg7 5. Rh5 Qd4 6. Rxg5 Rf7 7.
                                    Kb1 Kf8 8. Qe2 Bf6 9. Rg4
               17    70:22   1.88   1. Rg4 g5 2. Bxf4 exf4 3. Rh5 Qd4 4.
                                    Qxd4 Bxd4 5. Rgxg5+ Kf7 6. Rh7+ Ke8
                                    7. Rxc7 Rb8 8. Rg6 Kd8 9. Rh7 Be5 10.
                                    Bf5 b5 11. Rd7+ Ke8
              time=90:00  cpu=199%  mat=-1  n=2713942123  fh=22%  nps=502565
              ext-> checks=167874950 recaps=7425378 pawns=1230798 1rep=12970613
thrt:858857
              predicted=0  nodes=2713942123  evals=465463975
              endgame tablebase-> probes done=0  successful=0
              SMP->  split=2020  stop=328  data=9/64  cpu=179:59  elap=90:00

PFGA: EPD record: 3   ID: ECM.1169
         (3)   14->  68:37   3.24   1. Qh4+ Nh5 2. Bxd7 Bxd7 3. Ne4 Bb5
                                    4. g4 f6 5. Bxf6+ Rxf6 6. Nxf6 Bxf1
                                    7. gxh5 g5 8. Qe4 Bxh2+ 9. Nxh2 Bh3
               15    75:56     ++   1. Qh4+!!
              time=90:00  cpu=199%  mat=-1  n=2940854110  fh=11%  nps=544589
              ext-> checks=217091210 recaps=5256833 pawns=95536 1rep=15509470
thrt:771142
              predicted=0  nodes=2940854110  evals=233818681
              endgame tablebase-> probes done=0  successful=0
              SMP->  split=3402  stop=407  data=11/64  cpu=179:58  elap=90:00

PFGA: EPD record: 4   ID: ECM.1229
         (3)   13->  31:43  -0.53   1. ... Be5 2. f5 Rb6 3. Qd3 Bxh2 4.
                                    Na4 Rbb8 5. Bh4 Qe5 6. Qxa6 Rxf5 7.
                                    Rxf5 Qxf5 8. Qe2
         (2)   14    37:29  -0.43   1. ... Be5 2. f5 Rb6 3. Qd3 Bxh2 4.
                                    Kb1 Rfb8 5. b3 Nc5 6. Qh3 Be5 7. Bh4
                                    Qf8 8. Qe3 Bxc3 9. Qxc3
               14    65:48  -0.17   1. ... Rxb2 2. Kxb2 Ba3+ 3. Kxa3 Rb8
                                    4. Nb5 Rxb5 5. Bb4 a5 6. c3 Nxc3 7.
                                    Qxc3 axb4+ 8. Qxb4 Rxb4 9. Kxb4
         (2)   14->  71:50  -0.17   1. ... Rxb2 2. Kxb2 Ba3+ 3. Kxa3 Rb8
                                    4. Nb5 Rxb5 5. Bb4 a5 6. c3 Nxc3 7.
                                    Qxc3 axb4+ 8. Qxb4 Rxb4 9. Kxb4
              time=90:00  cpu=199%  mat=-1  n=2607920258  fh=4%  nps=482899
              ext-> checks=163042786 recaps=7179847 pawns=3210991 1rep=16227409
thrt:1590024
              predicted=0  nodes=2607920258  evals=421826891
              endgame tablebase-> probes done=0  successful=0
              SMP->  split=1208  stop=299  data=8/64  cpu=180:00  elap=90:00

PFGA: EPD record: 5   ID: ECM.1259
         (4)   13->  21:09   2.27   1. Nd5 cxd5 2. Bh6 Bg4 3. Qxg4 g6 4.
                                    Bxf8 Bxf8 5. Nc3 Na6 6. Rxd5 Nc5 7.
                                    Kb1 Rd8 8. Rf1
         (3)   14    30:18   2.44   1. Nd5 cxd5 2. Bh6 Bg4 3. Qxg4 g6 4.
                                    Bxf8 Bxf8 5. Nf6+ Kg7 6. Qc8 Qxa2 7.
                                    Qxb7 Bb4 8. Ne8+ Kf8 9. Qxb4+ Kxe8
                                    10. Qb5+ Kf8 11. Qxd5
              time=90:00  cpu=199%  mat=-1  n=2721910306  fh=6%  nps=504031
              ext-> checks=183256791 recaps=4588671 pawns=65789 1rep=17764086
thrt:1704873
              predicted=0  nodes=2721910306  evals=347834008
              endgame tablebase-> probes done=0  successful=0
              SMP->  split=1658  stop=338  data=9/64  cpu=179:59  elap=90:00

PFGA: EPD record: 6   ID: ECM.1291
         (3)   13->  14:54   0.86   1. f4 gxf4 2. gxf4 Ng4 3. Qd7 Rb8 4.
                                    Rd2 Qd8 5. Qf5 Rh6 6. Bc2 Kg8 7. Rde2
                                    Qc7
         (2)   14    17:17   0.72   1. f4 gxf4 2. gxf4 Ng4 3. Qd7 Rb8 4.
                                    Rd2 Qc5 5. Kh1 Rg8 6. Qf5 h4 7. Bd1
                                    Bxd4 8. Bxg4
               14    51:33   0.73   1. Nf3 Nxf3+ 2. Qxf3 h4 3. g4 Kg7 4.
                                    Re4 Rhc8 5. Rde1 Qc7 6. Qf5 Rd8 7.
                                    Bc4 Qd7 8. Qf3 Kg8
         (4)   14->  54:59   0.73   1. Nf3 Nxf3+ 2. Qxf3 h4 3. g4 Kg7 4.
                                    Re4 Rhc8 5. Rde1 Qc7 6. Qf5 Rd8 7.
                                    Bc4 Qd7 8. Qf3 Kg8
         (3)   15    65:17   0.76   1. Nf3 Nxf3+ 2. Qxf3 h4 3. g4 Kg7 4.
                                    Re3 Qc5 5. Rde1 Rhe8 6. Qe4 Rac8 <HT>
              time=90:00  cpu=199%  mat=0  n=2470142217  fh=28%  nps=457396
              ext-> checks=80734883 recaps=7325976 pawns=2152792 1rep=6165731
thrt:525712
              predicted=0  nodes=2470142217  evals=590841838
              endgame tablebase-> probes done=0  successful=0
              SMP->  split=1639  stop=373  data=10/64  cpu=179:59  elap=90:00

PFGA: EPD record: 7   ID: ECM.1545
         (4)   14->   4:47   2.30   1. cxb5 Bb7 2. Rdd1 f3 3. Kf2 Re8 4.
                                    Rxe8 Kxe8 5. Bb3 Rf4 6. Re1+ Re4 7.
                                    Rxe4+ Bxe4 8. Be6 g5 9. h3
               15     7:01     ++   1. cxb5!!
              time=90:00  cpu=199%  mat=0  n=3102501316  fh=0%  nps=574484
              ext-> checks=440321796 recaps=1541757 pawns=14773230 1rep=53733160
thrt:128571
              predicted=0  nodes=3102501316  evals=50781900
              endgame tablebase-> probes done=0  successful=0
              SMP->  split=2346  stop=279  data=13/64  cpu=179:59  elap=90:00

PFGA: EPD record: 8   ID: ECM.1574
         (2)   13->   6:37   0.58   1. Rfe1 Rae8 2. Qxe5 Qxe5 3. Rxe5 Ng4
                                    4. Rg5 Nxh2 5. Rd7 g6 6. Rxb7 Rxe6
                                    7. Rxa7 Rf2
               14    30:38   0.41   1. Rfe1 Nd5 2. Qxe5 Qxe5 3. Rxe5 Nxc3
                                    4. bxc3 Rf2 5. Rd2 Rxd2 6. Kxd2 Kf8
                                    7. Ke3 Ke7 8. h4 Rd8 9. a4
               14->  41:24   0.41   1. Rfe1 Nd5 2. Qxe5 Qxe5 3. Rxe5 Nxc3
                                    4. bxc3 Rf2 5. Rd2 Rxd2 6. Kxd2 Kf8
                                    7. Ke3 Ke7 8. h4 Rd8 9. a4
              time=90:00  cpu=199%  mat=-1  n=2626312791  fh=1%  nps=486329
              ext-> checks=154503691 recaps=10343152 pawns=13532858
1rep=15148744 thrt:823524
              predicted=0  nodes=2626312791  evals=521608900
              endgame tablebase-> probes done=0  successful=0
              SMP->  split=1299  stop=253  data=10/64  cpu=180:00  elap=90:00

PFGA: EPD record: 9   ID: ECM.1621
               13->  16:23  -0.42   1. ... Qb8 2. Qxb4 Qa7+ 3. d4 d5 4.
                                    Qa5 exd4 5. Kh1 Rxh2+ 6. Kxh2 Rh8+
                                    7. Kg3 Nxe4+ 8. Kf3 Rf8+ 9. Ke2 Ng3+
                                    10. Kd3 Rxf1 11. Qxd5+ Kc8 12. Bxg5
                                    Bxg5 13. Qxg5
               14    27:27  -0.42   1. ... Qb8 2. Qxb4 Qa7+ 3. d4 d5 4.
                                    Qa5 exd4 5. Kh1 Rxh2+ 6. Kxh2 Rh8+
                                    7. Kg3 Nxe4+ 8. Kf3 Rf8+ 9. Ke2 Ng3+
                                    10. Kd3 Rxf1 11. Qxd5+ Kc8 12. Bxg5
                                    Bxg5 13. Qxg5
               14->  34:06  -0.42   1. ... Qb8 2. Qxb4 Qa7+ 3. d4 d5 4.
                                    Qa5 exd4 5. Kh1 Rxh2+ 6. Kxh2 Rh8+
                                    7. Kg3 Nxe4+ 8. Kf3 Rf8+ 9. Ke2 Ng3+
                                    10. Kd3 Rxf1 11. Qxd5+ Kc8 12. Bxg5
                                    Bxg5 13. Qxg5
              time=90:00  cpu=199%  mat=-1  n=2331090612  fh=5%  nps=431672
              ext-> checks=112054105 recaps=7549654 pawns=2921497 1rep=9970016
thrt:530107
              predicted=0  nodes=2331090612  evals=501714256
              endgame tablebase-> probes done=0  successful=0
              SMP->  split=1326  stop=269  data=11/64  cpu=179:59  elap=90:00

PFGA: EPD record: 10   ID: ECM.1622
               16->  35:49   0.03   1. Bd2 h6 2. Nf3 Kh8 3. Rab1 Bc6 4.
                                    Qh4 Ng8 5. Bg5 Qd7 6. Nd2 Rfe8 7. c4
                                    dxc4 8. Nxc4 Qd5 9. Re4
               17    57:58   0.04   1. Bd2 h6 2. Nf3 Kh8 3. Rab1 Bc6 4.
                                    Qh4 Ng8 5. Bg5 Qd7 6. Rec1 a5 7. a3
                                    Rfe8 8. c4 a4 9. c5
               17->  75:47   0.04   1. Bd2 h6 2. Nf3 Kh8 3. Rab1 Bc6 4.
                                    Qh4 Ng8 5. Bg5 Qd7 6. Rec1 a5 7. a3
                                    Rfe8 8. c4 a4 9. c5
              time=90:00  cpu=199%  mat=0  n=2376340288  fh=1%  nps=440031
              ext-> checks=40104105 recaps=6609723 pawns=761413 1rep=5049530
thrt:450011
              predicted=0  nodes=2376340288  evals=578452868
              endgame tablebase-> probes done=0  successful=0
              SMP->  split=1122  stop=210  data=7/64  cpu=179:59  elap=90:00

Kind regards
Bernhard



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.