Author: Bruce Moreland
Date: 10:20:26 12/31/97
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Here is another message that includes information on how Deep Thought performed on this suite. bruce ------------------ From: mfb@cnam.cnam.fr (Marc-Francois Baudot) Newsgroups: rec.games.chess Subject: Re: Nolot's 11 difficult positions (possible spoilers) Date: 29 Jul 1994 11:44:00 GMT Organization: Conservatoire National des Arts et Metiers, Paris, France fhh@watson.ibm.com (Feng-Hsiung Hsu) writes: >Sometime ago, the following 11 positions collected by Pierre Nolot were >posted to rgc. Pierre claimed that no computers can solve any of them >in reasonable time (and no micros in even a few weeks). A long while back, he >might be right. At this point, a few of them are solvable even under >tournament time control. The ones that we tried overnight are all solvable >in a few hours. DT-2 was searching around 3 million nodes/sec during the >runs. The time probably would be reduced by 5-30 times for the harder >problems if the machine has a better quiescence search. I just phoned Pierre, and he admits he is very impressed by DT-2'sresults! So am I, and we thank you for the time you have spent on these positions. I'll post the solutions according to Pierre as given in Gambisco separately, but first I'll just give you his comments on DT's outstanding results (much much better than the best micros) >1 ;r3;q;b1;k/1;b4;p1/;p2;p;r2;p/3;n4/p;n;p1n1n1/6rp/1b3pp1/1b1qr1k1/40 >Source: Kasparov-Karpov, Lyon 1990. >Kasparov played Nh6 here. DT-2 agreed with Kasparov's analysis after >going down the line given in Informant, but could not find the move >on its own in one hour time. When letting it run overnight, it produced >Nh6 after 8 hours (but would play it with a 6 hours/move time control; that >is, it got first indication that the combination might work after about 6 >hours), with the variation 1. Nh6! c3 2. Nf5 cb2 3. Qg4 ... which wins for >white. Very good. This is not an easy one! >2 ;r4;r;k1/;p;p1;n1;p1;p/1;n;qP2;p1/2;b1p1b1/4nq2/1b3p2/pp2k2p/2r5/40 >Source: Bronstein-Ljubojevic, Petropolis 1973. >Solution is 1. Rc5! Nc5 2. Nf6 Kh8 3. Qh4... Solved under tournament >time control (3 minutes/move, plus extra time if the value for the move >is unstable). Plays it after 2 minutes. Actually spent 4.5 minutes before >the value stabilized to about a piece up. Excellent!! and this is not supposed to be an easy one. Your score proves you found it for the good reasons. >3 ;r2;q;k2;r/;p;p;p1;b1;p;p/2;n1;p3/3;pp1;n1/3p2;b1/2pb1nn1/pp4pp/r1bqk2r/40 >Source: Smagin-Sahovic, Biel 1990. >Solution move is 1. Ng5!. Verified that the move is sound by following >the published analysis, but could not play it within one hour time. This >is more a positional sac than what would be normally called tactics. Well, Pierre still calls it tactics! >4 ;r1;b1;k;b1;r/1;p1;n1;p;p;p/;p2;p;p;n2/6bb/2;qnp3/2n5/ppp2ppp/r2q1rk1/40 >Source: Keres-Kotov, Budapest 1950. >Solution: 1. Ne6 Qe6 2. Nd5 Kd8 3. Bg4. Plays it after 3.8 hours, would play >it under 2.5 hour/move time control. Very good! >5 ;r2;q;r;b1;k/1;p1;b2;p1/;p2;p;p;n1;p/8/3np3/1bn5/ppp3qp/1k3rr1/40 >Source: Spassky-Petrosian, Moskow 1969. >Took 4 hours to find e5!. 1. e5! de5 2. Ne4 Nh5 3. Qg6... More than a >piece up. The minimum time control needed to play it is around 2 hours/move. Very good, but 3.Qg4 is even stronger (spassky played Qg6) Hiarcs also finds this one, and also gives 3Qg6 >6 ;r;n;b;q;k2;r/1;p3;p;p;p/;p7/1n;pp;p3/qpp1p1;n1/p4n2/4k;bpp/r1b2b1r/41 >Source: Melaniuk-Ivanchuk, USSR 1988. >Ivanchuk played 1. ... ab5! which appears to be a sound positional sacrifice. >Calling this position a tactical one, however, is a little unfair on Pierre's >part. Ivanchuk, by the way, could not find the best continuations over the >board, but won it anyway due to Melaniuk's inaccurate defence. Could not >solve it in one hour. Probably a home preparation. The same move was >replayed 3 years later in some random tournament. All this is perfectly right, except that Pierre still thinks this is tactics. Very deep tactics. >7 1;r1;b;k2;r/2r2;p;p;p/;p3;p3/1;b2p2;q/4qp2/4n3/1b4pp/3r2k1/40 >8 - R - B K * - R >7 * - r - * P P P >6 P * - * P * - * >5 * B * - p - * Q >4 - * - * q p - * >3 * - * - n - * - >2 - b - * - * p p >1 * - * r * - k - > a b c d e f g h >Source: unknown. >This one we left the machine ran overnight. It found that 1. Rd8! wins. >1. Rd8! Kd8 2. Ra7 and if 2. ... Qe2 3. Qd4 Ke8 4. h3... Took 12 hours >to get the value back, but would have played it if the time control >is 6 hours/move. >8 ;r3;r;b;k1/;p;p;q2;p;p;p/2;b1;pb2/8/6q1/1p1b3p/p1p2pp1/r2r2k1/40 >White to move >8 R * - * R B K * >7 P P Q - * P P P >6 - * B * P b - * >5 * - * - * - * - >4 - * - * - * q * >3 * p * b * - * p >2 p * p * - p p * >1 r - * r * - k - > a b c d e f g h >Source: Gufeld-Osnos, USSR 1978. >The move played was 1. Bh7, but as it turns out 1. Bh7 might not be the >best move. Osnos defended poorly and got slaughtered. With best black >defence, white only maintains a positional edge after 1. Bh7 Kh7 2. Qh5 >Kg8 3. Rd4 Bf3! (with the idea of Qxc2, and then Q to king side to defend >the king). DT-2 prefers to play c4, which threatens Bh7 for real. >9 ;r4;r1;k/4;b;p;p;b/2;n1;p2;p/;p1;n1p3/1;p1;p1bnp/3p1np1/;qp2qpb1/2rr2k1/40 >White to move >8 R * - * - R - K >7 * - * - B P P B >6 - * N * P * - P >5 P - N - p - * - >4 - P - P - b n p >3 * - * p * n p - >2 Q p - * q p b * >1 * - r r * - k - > a b c d e f g h >Source: unknown. >After 9 minutes, it played 1. Nf6, expecting 1. ... Rfc8 2. Nh7 Kh7 3. Ra1 ... >The score was slightly nagative for white. On longer searches, it went up >to half a pawn and creeping up. >10 ;r1;b2;r;k1/1;p1;n;b;p;p;p/;p;q1;p4/3b4/p2np3/2n1;p3/1pp3pp/r2q1r1k/40 >White to move >8 R * B * - R K * >7 * P * N B P P P >6 P Q - P - * - * >5 * - * b * - * - >4 p * - n p * - * >3 * - n - P - * - >2 - p p * - * p p >1 r - * q * r * k > a b c d e f g h >Source: Van der Wiel-Ribli, Amsterdam 1980. >Solution is 1. Rf7 Rf7 2. Bf7 Kf7 3. Qh5. Plays it in less than 2 minutes, >score stablized within 5 minutes to a pawn plus. >11 ;r1;b3;k1/;p2;p1;np1/2;p;q;r1r;p/1;p2;p2p/2b1p;nq1/1p6/p1pp4/1k4r1/40 >White to move >8 R * B * - * K * >7 P - * P * N p - >6 - * P Q R * r P >5 * P * - P - * p >4 - * b * p N q * >3 * p * - * - * - >2 p * p p - * - * >1 * k * - * - r - > a b c d e f g h >Source: unknown >Be6 appears somewhat worse for white, but 1. Rh6 Nh6 2. Qg5 Nf7 3. Qd8 appears >to be a repetition draw or slightly ahead for white. Plays 1. Rh6 after >5 minutes, thought white was slightly ahead, but going down the line, it >appeared that black had enough pressure for a draw.
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