Author: Chessfun
Date: 03:26:34 11/20/01
Go up one level in this thread
On November 20, 2001 at 06:08:18, Uri Blass wrote: >On November 20, 2001 at 05:49:02, Uri Blass wrote: > >>On November 20, 2001 at 05:02:24, Jouni Uski wrote: >> >>>It's not so easy position: even the mighty Yace wants to play -Rd5 after >>>20 minutes and 300 000 000 nodes. It's not so easy to find this line: >>> >>>1.- Rd5 2. Rxd5 cxd5 3. a4 Kf6 4. b5 axb5 5. c6 bxc6 6. a5 Ke6... >>> >>>BTW is it sure, that Rd5 is losing? Can black improve? >>> >>>Jouni ><snipped> >>I am not sure if Rd5 is losing at least in comp-comp game >> >>Here is a drawn position that can happen in comp-comp game >>many plies after the root >>3.a4 Kf6 4.b5 Ke6 5.c6 Kd6 6.cxb7 Kc7 7.bxa6 g5 8.h4 f5 9.Ke3 f4+ 10.Kf3 Kb8 >>11.hxg5 hxg5 12.h3 > >It leads to the following test position > >How much time does your program need to avoid axb5 and find a king move that >gives at least practical chances for a draw(I did not analyze it to be sure that >it is a draw)? > >New position >[D]8/1p3p2/p4kpp/1PPp4/P7/7P/5K1P/8 b - - 0 1 > >Analysis by Yace 0.99.56: > >4...axb5 5.axb5 > -+ (-1.74) Depth: 1 00:00:04 >4...h5 > -+ (-1.84) Depth: 1 00:00:04 >4...g5 > -+ (-1.88) Depth: 1 00:00:04 >4...Ke6 > -+ (-1.90) Depth: 1 00:00:04 >4...Ke5 > -+ (-2.04) Depth: 1 00:00:04 >4...Ke5 5.Ke3 > -+ (-1.79) Depth: 2 00:00:04 >4...Ke5 5.c6 g5 6.bxa6 > µ (-1.32) Depth: 3 00:00:04 >4...Ke5 5.c6 bxc6 > µ (-0.84) Depth: 3 00:00:04 >4...axb5 5.Ke3 Ke5 > -+ (-1.76) Depth: 3 00:00:04 >4...axb5 5.axb5 Ke5 6.Ke3 > -+ (-1.76) Depth: 3 00:00:04 >4...axb5 5.axb5 Ke5 6.c6 bxc6 > -+ (-1.84) Depth: 4 00:00:04 >4...axb5 5.axb5 Ke6 6.Ke3 f5 7.c6 bxc6 > -+ (-1.91) Depth: 5 00:00:04 5kN >4...axb5 5.axb5 Ke6 6.b6 Kd7 7.Ke3 f5 8.Kd4 > -+ (-1.64) Depth: 6 00:00:04 33kN >4...axb5 5.axb5 Ke6 6.b6 Kd7 7.Ke3 f5 8.Kd4 Ke6 > -+ (-1.83) Depth: 7 00:00:04 86kN >4...axb5 5.axb5 Ke6 6.b6 Kd7 7.Ke3 f5 8.Kd4 Ke6 9.c6 > -+ (-1.70) Depth: 8 00:00:04 240kN >4...axb5 5.axb5 Ke6 6.b6 Kd7 7.Ke3 f5 8.h4 h5 9.Kd4 Ke6 > -+ (-1.83) Depth: 9 00:00:05 562kN >4...axb5 5.axb5 Ke6 6.Ke3 f5 7.b6 Kd7 8.h4 h5 9.Kd4 Ke6 10.c6 > -+ (-1.70) Depth: 10 00:00:07 1432kN >4...axb5 5.axb5 Ke6 6.Ke3 f5 7.Kd4 f4 8.h4 Kd7 9.h3 f3 10.Ke3 g5 11.hxg5 hxg5 >12.Kxf3 > -+ (-1.88) Depth: 11 00:00:10 3215kN >4...axb5 5.c6 bxc6 6.a5 b4 7.Ke3 b3 8.Kd2 d4 9.a6 d3 10.Kxd3 Ke5 11.a7 b2 12.Kc2 >Kd6 > -+ (-1.51) Depth: 12 00:00:17 7322kN >4...axb5 5.c6 bxc6 6.a5 b4 7.Ke3 b3 8.Kd2 d4 9.a6 b2 10.Kc2 Ke5 11.Kxb2 d3 12.a7 >d2 13.Kc2 Kd6 > µ (-1.17) Depth: 13 00:00:24 11356kN >4...axb5 5.c6 bxc6 6.a5 b4 7.Ke3 b3 8.Kd2 b2 9.Kc2 Ke6 10.a6 Ke7 11.a7 b1R >12.a8Q h5 > µ (-0.77) Depth: 14 00:00:36 18217kN >4...axb5 5.c6 bxc6 6.a5 b4 7.Ke3 b3 8.Kd2 b2 9.Kc2 b1Q+ 10.Kxb1 g5 11.a6 g4 >12.hxg4 Kg5 13.a7 Kxg4 > = (0.23) Depth: 14 00:00:37 18713kN >4...axb5 5.c6 bxc6 6.a5 b4 7.Ke3 b3 8.Kd2 b2 9.Kc2 d4 10.a6 d3+ 11.Kxb2 d2 >12.Kc2 d1Q+ 13.Kxd1 Ke5 > ² (0.43) Depth: 14 00:00:41 21052kN >4...axb5 5.c6 bxc6 6.a5 b4 7.Ke3 b3 8.Kd2 b2 9.Kc2 Ke6 10.a6 g5 11.a7 g4 12.a8Q >Kf5 > ± (0.83) Depth: 15 00:01:06 34581kN >4...axb5 5.c6 bxc6 6.a5 b4 7.Ke3 b3 8.Kd2 g5 9.a6 g4 10.hxg4 h5 11.gxh5 c5 12.a7 >b2 13.Kc2 b1R 14.a8Q Rd1 > +- (1.83) Depth: 15 00:01:07 35141kN >4...axb5 5.c6 bxc6 6.a5 b4 7.Ke3 > +- (1.83) Depth: 15 00:01:11 37456kN >4...axb5 5.c6 bxc6 6.a5 b4 7.Ke3 h5 8.Kd2 g5 9.a6 c5 10.a7 Kf5 > +- (2.23) Depth: 16 00:01:56 62191kN >4...axb5 5.c6 bxc6 6.a5 b4 7.Ke3 h5 8.Kd2 b3 9.a6 b2 10.Kc2 h4 11.a7 Kf5 12.a8Q >Ke4 > +- (3.23) Depth: 16 00:01:59 63931kN >4...axb5 5.c6 bxc6 6.a5 b4 7.Ke3 h5 8.Kd2 b3 9.a6 c5 10.a7 c4 11.a8Q Ke5 12.Qe8+ >Kf6 13.Qd7 b2 14.Qd6+ > +- (3.72) Depth: 16 00:02:19 75285kN >4...Ke6 5.c6 Kd6 6.cxb7 Kc7 7.b8Q+ Kxb8 8.b6 a5 9.h4 Kb7 10.Kf3 > +- (3.71) Depth: 16 00:03:03 99101kN >4...Ke6 5.c6 Kd6 6.cxb7 Kc7 7.bxa6 f5 8.Ke2 g5 9.Ke3 h5 10.h4 g4 11.Kf4 d4 12.a5 >Kb8 13.Kg5 > +- (3.28) Depth: 16 00:04:19 140272kN > >(Blass, Tel-aviv 20.11.2001) > > >Uri I think you'll find the original position after Rd5 is lost for black. As is the above after Ke6. From the original position. 36. Rxd5 cxd 37. a4 Kf6 38. b5 to yours Ke6 39.c6 Kd6 40.cxb7 Kc7 41.bxa6 f5 42. Ke2 g5 43. Ke3 h5 44. h4 g4 45. Kf4 d4 46. a5 Kb8 After this line 47. Kxd5 Wins in a few moves. Sarah.
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