Author: Uri Blass
Date: 15:02:24 09/12/01
Go up one level in this thread
On September 12, 2001 at 17:00:52, Dann Corbit wrote: >On September 12, 2001 at 16:45:15, Uri Blass wrote: > >>On September 12, 2001 at 16:08:11, Dann Corbit wrote: >> >>>On September 12, 2001 at 10:45:44, leonid wrote: >>> >>>>On September 12, 2001 at 10:34:41, leonid wrote: >>>> >>>>>[D]Q6r/1prpbqk1/1Q4q1/1Q1nn1p1/1Q1NN1p1/1R4q1/1BBQQRp1/K6b w - - >>>>> >>>>>Please indicate your result. >>> >>>According to chest, it's not a mate in 8. >>> >>>Crafty can't spot it, but I did not expect 17+ ply to be exhausted: >>>EPD Kit revision date: 1996.04.21 >>>unable to open book file [e:\crafty\release/books.bin]. >>>hash table memory = 192M bytes. >>>pawn hash table memory = 80M bytes. >>>EGTB cache memory = 32M bytes. >>>draw score set to 0.00 pawns. >>>choose from book moves randomly (using weights.) >>>choose from 5 best moves. >>>book learning enabled >>>result learning enabled >>>position learning enabled >>>threshold set to 9 pawns. >>>5 piece tablebase files found >>>19045kb of RAM used for TB indices and decompression tables >>> >>>Crafty v18.10 >>> >>>White(1): st 999 >>>search time set to 999.00. >>>White(1): epdpfga \t.epd t.out >>>PFGA: EPD record: 1 >>>middle-game phase >>> clearing hash tables >>> time surplus 0.00 time limit 16:39 (16:39) >>> nss depth time score variation (1) >>> 1 0.03 26.76 1. Rxf7+ Qxf7 >>> 1-> 0.05 26.76 1. Rxf7+ Qxf7 >>> 2 0.05 26.75 1. Rxf7+ Qxf7 2. Rxg3 Rxa8+ >>> 2-> 0.19 26.75 1. Rxf7+ Qxf7 2. Rxg3 Rxa8+ >>> 3 0.20 -- 1. Rxf7+ >>> 3 0.23 24.14 1. Rxf7+ Qxf7 2. Qxh8+ Kxh8 3. Qh6+ >>> Kg8 4. Rxg3 Bxb4 5. Qdxg5+ >>> 3-> 0.63 24.14 1. Rxf7+ Qxf7 2. Qxh8+ Kxh8 3. Qh6+ >>> Kg8 4. Rxg3 Bxb4 5. Qdxg5+ >>> 4 0.79 24.14 1. Rxf7+ Qxf7 2. Qxh8+ Kxh8 3. Qh6+ >>> Kg8 4. Rxg3 Bxb4 5. Qdxg5+ >>> 4-> 2.13 24.14 1. Rxf7+ Qxf7 2. Qxh8+ Kxh8 3. Qh6+ >>> Kg8 4. Rxg3 Bxb4 5. Qdxg5+ >>> 5 2.17 ++ 1. Rxf7+!! >>> 5 3.91 26.23 1. Rxf7+ Qxf7 2. Qxh8+ Kxh8 3. Rxg3 >>> Bxb4 4. Qh6+ Kg8 5. Qdxg5+ Ng6 6. Qbxd5 >>> 5-> 8.16 26.23 1. Rxf7+ Qxf7 2. Qxh8+ Kxh8 3. Rxg3 >>> Bxb4 4. Qh6+ Kg8 5. Qdxg5+ Ng6 6. Qbxd5 >>> 6 8.37 ++ 1. Rxf7+!! >>> 6 19.60 26.77 1. Rxf7+ Qxf7 2. Qxh8+ Kxh8 3. Qh6+ >>> Kg8 4. Nf6+ Nxf6 5. Qdxg5+ Ng6 6. Qhxg6+ >>> Qxg6 7. Qxg6+ Kh8 8. Rxg3 Bxb4 9. Qxb4 >>> 6-> 38.74 26.77 1. Rxf7+ Qxf7 2. Qxh8+ Kxh8 3. Qh6+ >>> Kg8 4. Nf6+ Nxf6 5. Qdxg5+ Ng6 6. Qhxg6+ >>> Qxg6 7. Qxg6+ Kh8 8. Rxg3 Bxb4 9. Qxb4 >>> 7 40.59 ++ 1. Rxf7+!! >>> 7 2:39 28.64 1. Rxf7+ Qxf7 2. Nf5+ Qxf5 3. Qxh8+ >>> Kxh8 4. Qh6+ Qh7 5. Qxh7+ Kxh7 6. Nxg3+ >>> Ng6 7. Qbd4 Bc5 >>> 7-> 3:37 28.64 1. Rxf7+ Qxf7 2. Nf5+ Qxf5 3. Qxh8+ >>> Kxh8 4. Qh6+ Qh7 5. Qxh7+ Kxh7 6. Nxg3+ >>> Ng6 7. Qbd4 Bc5 >>> 8 3:37 ++ 1. Rxf7+!! >>> time=16:39 cpu=99% mat=22 n=589487968 fh=99% nps=590k >>> ext-> chk=80125742 cap=1032919 pp=36146 1rep=5779692 mate=87 >>> predicted=0 nodes=589487968 evals=3796048 >>> endgame tablebase-> probes done=0 successful=0 >>> >>>So tell me, what's the solution? >>> >>>Pretty diagram, by the way. >> >>Crafty can solve it. >> >>I gave it the first move in the main line(Rxf7+) >>and after every legal move it can see a forced mate >> >>1.Rxf7+ Qxf7 [1...Kxf7 2.Qxd5+ #4/5 2 ; >>1...Kh6 2.Qxh8# #1/5 2 ; >>1...Nxf7 2.Nf5+ #6/5 2 ] 2.Qxh8+ #10/8 1:47 >> >>1.Rxf7+ Qxf7 is the main line and it needs some time to >>see mate in 10 after 1.Rxf7+ Qxf7 >> >>It has no problem to see shorter mate after all the other legal moves. > >Unforutnately, that's NOT the solution. It's Qxg6 according to leonid. Rxf7 is mate in 11 if there is no bug in Crafty so it is a solution for the mate problem. I did not say that it is the only solution and I did not say that Rxf7 leads to the shortest mate. Uri
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