Author: Robert Hyatt
Date: 12:56:09 06/06/99
Go up one level in this thread
On June 06, 1999 at 10:40:34, Michel Langeveld wrote: >I have found a position which the nodecount does not match sigma nodecount of >all succesors. > >Nodecount main position: 398 nodes >Sigma of all successors : 399 nodes (1x20+2x19+18x18+1x17) > >Conclusion: one node is lost in the mainposition using perft. > >I have included 2 scripts to examine the problem yourself. your conclusion is wrong. If you will carefully check your FEN, you will find that one of the lines has a misplaced pawn. _PLEASE_, before you report a bug, be _sure_ that the bug is not yours. I spent two hours looking at this before I modified the code to spit out a FEN for each position, and then discovered that one of yours was wrong (I think it is the last one). I don't mind searching for bugs, but when it wastes two hours... Bob > >--- script 1: to calculate the main position total is (398 nodes) --- >log off >ponder=off >setboard rnbqkbnr/2pppppp/p7/Pp6/8/8/1PPPPPPP/RNBQKBNR/ w b6 >perft 2 >exit >--- end script 1 --- > >--- script 2: to calculate all successor nodes (total is 399)--- >log off >ponder=off >setboard rnbqkbnr/2pppppp/p7/Pp6/8/8/RPPPPPPP/1NBQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/R7/1PPPPPPP/1NBQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/R7/8/1PPPPPPP/1NBQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/2N5/1PPPPPPP/R1BQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/N7/1PPPPPPP/R1BQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/7N/1PPPPPPP/RNBQKB1R/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/5N2/1PPPPPPP/RNBQKB1R/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/1P6/8/2PPPPPP/RNBQKBNR/ b b3 >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/1P6/2PPPPPP/RNBQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/2P5/8/1P1PPPPP/RNBQKBNR/ b c3 >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/2P5/1P1PPPPP/RNBQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/3P4/8/1PP1PPPP/RNBQKBNR/ b d3 >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/3P4/1PP1PPPP/RNBQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/4P3/8/1PPP1PPP/RNBQKBNR/ b e3 >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/4P3/1PPP1PPP/RNBQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/5P2/8/1PPPP1PP/RNBQKBNR/ b f3 >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/5P2/1PPPP1PP/RNBQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/6P1/8/1PPPPP1P/RNBQKBNR/ b g3 >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/6P1/1PPPPP1P/RNBQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/7P/8/1PPPPPP1/RNBQKBNR/ b h3 >perft 1 >setboard rnbqkbnr/2pppppp/p7/Pp6/8/7P/1PPPPPP1/RNBQKBNR/ b >perft 1 >setboard rnbqkbnr/2pppppp/pP6/1p6/8/8/1PPPPPPP/RNBQKBNR/ b >perft 1 >exit >--- end of script 2 ---
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