Author: leonid
Date: 09:38:50 09/03/00
Go up one level in this thread
On September 03, 2000 at 11:32:09, Bert van den Akker wrote: >On September 02, 2000 at 17:08:20, leonid wrote: > >>Hello! >> >>Please solve these two positions and say minimum number of moves that lead to >>it. >> >> 1r2k2r/1b3pbp/1NPqN1n1/1P1Q4/1P2P3/P3B3/5PP1/R3KB1R White to go. >> >> 6KQ/3B2Q1/QQQQQQQ1/5Nbn/qqqqq1q1/5qqk/8/8 White to go. >> >>It will be good if you will indicate all main parameters of your trial. At >>least, I see them this way: >> >>Name of your program. Hash table size. >>In what way (if you know) position was solved. Selective search or brute force >>search. >>Time for each way of search. >>CPU and its speed. >> >>If you could come with some of your "crazy" (fantasy) position or normal one, it >>will be good. When you will depose your, try to make them between 5 and 9 moves >>mate. That deep you still can expect reasonable time to be solved by brute force >>on our computers. >> >>Thanks in advance, >>Leonid. > > >Hello Leonid, > >My program is basicly brute force but the extensions and null moves makes it >also selective. Interesting since it very different from my mate search. >Depending on the positions mates till 45 plies can be >solved in seconds. In this cases there are many checks and ony one reply on that >checks. > >Here are my the results of the second positions: >[D] 6KQ/3B2Q1/QQQQQQQ1/5Nbn/qqqqq1q1/5qqk/8/8 w > >Name program: Bobo >Hash table size: 262144 entries >recursiv null move on Do you use null move when solving the mate positions? >extensions used: >Check extension Maybe, it is what I have. My program, when look for mate, search through indicated number of moves. Those moves can be of every kind possible. >Threat extension >Single move out of check extension in normal search > >Single move out of check extension in quiet search > > >Nf5xg3 >(score= 1941) (depth= 1/1) >(time = 19.9900000000052) >(evaluations= 401986) >Nf5xd4 >(score= 1942) (depth= 1/1) >(time = 26.5300000000061) >(evaluations= 530496) >Nf5xd4 >(score= 1943) (depth= 1/1) >(time = 32.0200000000041) >(evaluations= 637640) >Qa6xa4 >(score= 1944) (depth= 1/1) >(time = 40.2100000000064) >(evaluations= 798971) >Qa6xa4 Qb4xd6 Qa4xc4 Qd4xc4 Qc6xe4 Qd6xb6 Qe6xc4 Qf3xe4 Qc4xe4 Qg4xe4 >Qf6xb6 >(score= 1954) (depth= 1/11) >(time = 60.0300000000061) >(evaluations= 1191561) >Qa6xc4 >(score= 1955) (depth= 1/1) >(time = 65.2000000000044) >(evaluations= 1291614) >Qa6xc4 Qb4xd6 Qc6xd6 Qd4xd6 >(score= 1963) (depth= 1/4) >(time = 76.9500000000044) >(evaluations= 1523217) >Qc6xc4 >(score= 1964) (depth= 1/1) >(time = 93.4300000000003) >(evaluations= 1846206) >Qc6xc4 Qd4xQ6 Qc4xe4 Qd6xe6+ Ld7xe6 >(score= 1965) (depth= 1/5) >(time = 102.330000000002) >(evaluations= 2013926) >Qc6xe4 >(score= 1966) (depth= 1/1) >(time = 108.090000000004) >(evaluations= 2122987) >Qc6xe4 Qd4xQ6 Pf5xd6 Qc4xe6+ Ld7xe6 >(score= 1967) (depth= 1/5) >(time = 118.040000000001) >(evaluations= 2302593) >Qc6xe4 Qd4xe4 Pf5xg3 Qe4xg6 Qf6xg6 Qg4xe6+ Ld7xe6+ Kh3-g2 >(score= 1946) (depth= 2/8) >(time = 102.709999999999) >(evaluations= 2114069) >Qg6xh5+ >(score= 1947) (depth= 2/1) >(time = 123.139999999999) >(evaluations= 2482105) >Qg6xh5+ Qg4xh5 Qh8xh5+ Kh3-g2 Qc6xe4 Qd4xe4 Qd6xg3+ Qf3xg3 Pf5xg3 >(score= 2309) (depth= 2/9) >(time = 281.709999999999) >(evaluations= 5391421) >Qg6xh5+ >(score= 2537) (depth= 3/1) >(time = 25.3699999999953) >(evaluations= 513635) >Qg6xh5+ Qg4xh5 Qh8xh5+ Qg3-h4 Pf5xh4+ Qc4xe6+ Bd7xe6+ Qe4xe6+ Qd6xe6+ Qf3-g4 >Qe6xg4+ Qd4xg4 Qh5xg4+ Kh3xg4 Qb6xb4+ Kg4-g3 Qf6xg5+ Kg3-h2 Qa6-e2+ Kh2-h3 >Qe2-f3+ Kh3-h2 Qf3-f4+ Kh2-h3 Qf4-f5+ Kh3-h2 Ph4-f3+ Kh2-h1 Qf5-h7+ >(score= 19971) (depth= 3/29) >(time = 135.769999999997) > >Mate in 15 moves The most probable is that your program is more that solid. This kind of position could kill many good programs. It is very heavy. Average number of nodes in each ply is 52. It was said by average nodes counter 8 plies deep. Occasional number of nodes in ply reach beyond 100 moves. I even don't know exactly number of minimum moves that lead to the mate in this position. When tried to find the move, I only found that mate existe for sure in 11 moves. Expected that somebody else with better branching factor will say final number. Since I could not solve this position by very quick selective search, I never even tried to reach minimum number by brute force. It could be too long. I know only that one selective search find mate in 11 moves in 8 sec. Computer AMD 400M, llchess solver. Leonid.
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