🔍 Countermoves

[eduherminio]

✅ Identify move by SourceSquare, TargetSquare:

Test  | search/countermoves
Elo   | 4.89 +- 3.34 (95%)
SPRT  | 8.0+0.08s Threads=1 Hash=32MB
LLR   | 2.90 (-2.25, 2.89) [0.00, 3.00]
Games | 22944: +7352 -7029 =8563
Penta | [874, 2587, 4328, 2708, 975]
https://openbench.lynx-chess.com/test/478/

✅ Align with existing implementation of identifying moves by Piece, TargetSquare:

Test  | search/countermoves
Elo   | 2.01 +- 4.31 (95%)
SPRT  | 8.0+0.08s Threads=1 Hash=32MB
LLR   | 2.90 (-2.25, 2.89) [-5.00, 0.00]
Games | 13338: +4217 -4140 =4981
Penta | [508, 1500, 2562, 1605, 494]
https://openbench.lynx-chess.com/test/485/

✅ Flatten countermoves array: #860 (4.49 +- 3.10)

❌ Clear countermoves per search instead of per new game

Test  | search/countermoves-clearing-2
Elo   | -0.38 +- 2.33 (95%)
SPRT  | 8.0+0.08s Threads=1 Hash=32MB
LLR   | -2.26 (-2.25, 2.89) [0.00, 3.00]
Games | 45014: +14144 -14193 =16677
Penta | [1728, 5053, 8914, 5164, 1648]
https://openbench.lynx-chess.com/test/486/

Total:

8+0.08

Score of Lynx-search-countermoves-3342-win-x64 vs Lynx 3338 - main: 6644 - 6345 - 7854  [0.507] 20843
...      Lynx-search-countermoves-3342-win-x64 playing White: 4680 - 1849 - 3893  [0.636] 10422
...      Lynx-search-countermoves-3342-win-x64 playing Black: 1964 - 4496 - 3961  [0.379] 10421
...      White vs Black: 9176 - 3813 - 7854  [0.629] 20843
Elo difference: 5.0 +/- 3.7, LOS: 99.6 %, DrawRatio: 37.7 %
SPRT: llr 2.9 (100.2%), lbound -2.25, ubound 2.89 - H1 was accepted

40+0.4

Score of Lynx-search-countermoves-3342-win-x64 vs Lynx 3338 - main: 3921 - 3844 - 5535  [0.503] 13300
...      Lynx-search-countermoves-3342-win-x64 playing White: 2987 - 953 - 2711  [0.653] 6651
...      Lynx-search-countermoves-3342-win-x64 playing Black: 934 - 2891 - 2824  [0.353] 6649
...      White vs Black: 5878 - 1887 - 5535  [0.650] 13300
Elo difference: 2.0 +/- 4.5, LOS: 80.9 %, DrawRatio: 41.6 %
SPRT: llr 0.289 (10.0%), lbound -2.25, ubound 2.89

python3.exe .\sprt.py -w 3921 -l 3844 -d 5535 -e0 -5 -e1 0
ELO: 2.01 +- 4.51 [-2.49, 6.52]
LLR: 3.18 [-5.0, 0.0] (-2.94, 2.94)
H1 Accepted