Author: Uri Blass
Date: 08:27:37 01/28/02
Go up one level in this thread
On January 28, 2002 at 10:43:15, Roy Eassa wrote: >On January 27, 2002 at 22:08:06, Andrew Smith wrote: > >>On January 27, 2002 at 19:08:07, Roy Eassa wrote: >> >>>On January 27, 2002 at 18:22:33, Andrew Smith wrote: >>> >>>>I don't know about how well programs are to find draws by stalemate. It looks >>>>like some have big problems. The lines begins with Rc4. I guess if your program >>>>finds the first move the rest should follow. >>>> >>>>[D]8/p7/P2p1p2/3n4/R2P3K/1p2P1N1/P1p2P1k/Rn6 w KQkq - 0 1 >>> >>> >>>I doubt that any current program/computer can find the draw. >>> >>>This is what I came up with (using Fritz 7 to help of course!): >>> >>>1.Rc4! b2 2.Rxc2 bxa1Q 3.f3+! >>> >>> [3.f4+ Kg1 4.Kh3 Nxe3 5.Rh2 f5! >>> (5...d5? 6.f5 Qc3 7.Ne2+ Kf1 8.Nxc3 Nxc3 9.Rb2 Ne2 >>> 10.Rb6 Ng1+ 11.Kg3 Nxf5+ 12.Kf4 Nxd4 13.Rxf6 Ke2 >>> 14.Ke5 Kd3 15.Rf7 Nge2 16.Kxd5 Nc3+ 17.Kd6 Nxa2 =) >>> 6.Ne2+ Kf1 7.Ng3+ Ke1 8.Re2+ Kd1 -+] >>> >>>3...Kg1 4.Kh3! Nxe3 5.Rh2 f5 6.f4 d5 7.a3! Qxa3 >>> >>> [7...Qc3? 8.Ne2+ Kf1 9.Nxc3 Nxc3 10.Rb2 Ne2 11.Rb7 Nxf4+ >>> 12.Kh4 Nc4 13.Rxa7 +-] >>> >>>8.Rg2+ Nxg2 stalemate ½-½ >>> >>> >>>Is this correct? >> >>Just curious, can you post the analysis? I want to see the evals, and depth etc. > > >I obtained the above analysis by manually going up and down the tree of >possibilities using Fritz in analysis mode. I.e., Fritz definitely did NOT see >the entire thing in advance, or anything close. Thus my comment above, "I doubt >that any current program/computer can find the draw." Even given several hours >on a fast PC, I don't think Fritz or any other engine would see this through to >the draw. I suspect that if you give them some hours they will have no choice but to see the right move Here is yace's analysis on p800(more than 16 minutes) You can see that axb3 fails low every iteration(I suspect that after one of the next fail lows it is going to have no choice but to change it's mind to Rc4) New position 8/p7/P2p1p2/3n4/R2P3K/1p2P1N1/P1p2P1k/Rn6 w - - 0 1 Analysis by Yace 0.99.56: 1.Rxb1 cxb1Q 2.axb3 Qxb3 -+ (-3.70) Depth: 1 00:00:04 1.axb3 c1Q µ (-0.89) Depth: 1 00:00:04 1.Rc4 +- (6.12) Depth: 1 00:00:04 1.Rc4 b2 2.e4 +- (5.31) Depth: 2 00:00:04 1.Rc4 b2 2.Nf1+ Kg2 +- (5.07) Depth: 2 00:00:04 1.Rc4 b2 2.Nf1+ Kg2 +- (5.07) Depth: 3 00:00:04 1.Rc4 b2 2.Rxc2 bxa1Q 3.f3+ Nd2 4.Rxd2+ Kg1 -+ (-2.14) Depth: 4 00:00:04 1.Rc4 b2 2.Rc5 bxa1Q 3.Rxd5 -+ (-4.37) Depth: 4 00:00:04 1.Rc4 b2 2.Rxb1 cxb1Q 3.a3 -+ (-4.49) Depth: 4 00:00:04 1.axb3 c1Q -+ (-4.47) Depth: 4 00:00:04 1.axb3 c1Q 2.Nf5 Qb2 3.Nxd6 Qxb3 ³ (-0.70) Depth: 4 00:00:04 1.Nf1+ Kg2 2.Nd2 c1N ³ (-0.69) Depth: 4 00:00:04 1.Nf1+ Kg2 2.Nd2 c1Q 3.Nxb1 Kxf2 4.axb3 Kxe3 = (0.08) Depth: 4 00:00:04 1.Nf1+ Kg2 2.Nd2 c1Q 3.Nxb3 ³ (-0.32) Depth: 5 00:00:04 8kN 1.Nf1+ Kg2 2.Nd2 c1Q 3.Kg4 µ (-1.32) Depth: 5 00:00:04 8kN 1.Nf1+ Kg2 2.axb3 c1Q 3.Ra5 Ne7 4.Ng3 -+ (-1.60) Depth: 5 00:00:04 8kN 1.axb3 Nxe3 2.fxe3 Kg2 µ (-1.35) Depth: 5 00:00:04 8kN 1.axb3 c1Q 2.Ra5 Qc3 3.Ne4 Qxb3 ³ (-0.64) Depth: 5 00:00:04 8kN 1.axb3 c1Q 2.R1a2 Qc7 3.f3+ Kg1 4.e4 Qh7+ 5.Kg4 µ (-0.79) Depth: 6 00:00:04 74kN 1.axb3 c1Q 2.Ra5 Qc8 3.Kh5 Qh3+ 4.Kg6 Qg4+ 5.Kh7 Qh4+ 6.Kg8 Nbc3 µ (-0.97) Depth: 7 00:00:04 94kN 1.axb3 c1Q 2.R1a2 Kg2 3.Rc4 Nbc3 4.Rc6 Nxa2 5.Rxc1 µ (-1.00) Depth: 8 00:00:05 477kN 1.axb3 c1Q 2.R1a2 Kg2 3.Rc4 Nbc3 4.Nf1 Qxf1 5.Rb2 µ (-1.40) Depth: 9 00:00:07 890kN 1.axb3 c1Q 2.R1a2 Kg2 µ (-1.40) Depth: 9 00:00:07 890kN 1.axb3 c1Q 2.R4a2 Kg2 3.Kh5 Qd1+ 4.Kh6 Ndc3 5.Ra3 Kxf2 6.Nf5 Nxa3 7.Rxd1 -+ (-1.77) Depth: 10 00:00:13 3101kN 1.axb3 c1Q 2.R4a2 Kg2 3.Kh5 Nb4 4.Re2 Nc2 5.Ra2 Nxd4 6.Reb2 Qc5+ 7.Kh6 -+ (-1.82) Depth: 11 00:00:25 7630kN 1.axb3 c1Q 2.R4a2 Kg2 3.Kh5 Ne7 4.Kh6 Qc8 5.f3+ Kxg3 6.Kh7 Kxf3 7.Kh6 -+ (-2.22) Depth: 12 00:01:17 26895kN 1.axb3 c1Q 2.R4a2 Kg2 3.Kh5 Ne7 4.Kh6 Qc8 5.Kg7 Nc3 6.e4 Nxa2 7.Rxa2 -+ (-2.48) Depth: 12 00:01:27 30175kN 1.axb3 c1Q 2.R4a2 Kg2 3.Kh5 Ndc3 4.Ra5 Kxf2 5.Nf5 Qg1 6.Rxb1 Nxb1 7.Nxd6 Kxe3 8.Ne8 -+ (-2.88) Depth: 13 00:03:32 76767kN 1.axb3 c1Q 2.R4a2 Kg2 3.Kh5 Ndc3 4.Ra5 Kxf2 5.Nf5 Qg1 6.Nh6 Ke2 7.Rf5 Qh2+ 8.Kg6 Kxe3 -+ (-2.93) Depth: 13 00:04:33 98685kN 1.axb3 c1Q 2.R4a2 Kg2 3.Kh5 Ne7 4.Kh6 Qc8 5.Kg7 Qg8+ 6.Kxf6 Nd5+ 7.Kf5 Kh3 8.Ke4 Nbc3+ 9.Kd3 Nxa2 10.e4 Ndb4+ 11.Kd2 -+ (-3.33) Depth: 14 00:07:27 164309kN 1.axb3 c1Q 2.R4a2 Kg2 3.Kh5 Ne7 4.Nf5 Nxf5 5.Kg6 Ne7+ 6.Kxf6 Nd5+ 7.Ke6 Nb4 8.Ra4 Nc2 9.Rc4 Kxf2 -+ (-3.68) Depth: 14 00:13:32 299421kN (Blass, Tel-aviv 28.01.2002) Uri
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