SierC5BCant
[ Sierżant [1] Sierżant, (Sierzant)
a WinBoard compliant chess engine by Mariusz Rostek, written in C++ and first released in November 2004. Sierżant was described in Mariusz’ 2008 Diploma thesis [2]. It is the successor of the weaker Szeregowiec, and predecessor of the stronger Porucznik - in dependence to the Polish Armed Forces ranking.
Selected Games
PCCC 2006, round 3, Sierżant - nanoSzachy [3]
Description
Board Representation
The board is represented by a 10x10 array, move generation is done in conjunction with piece lists and Table-driven Move Generation.
Search
Sierżant performs PVS alpha-beta with null-move pruning and razoring inside an iterative deepening loop, and extends consecutive checks up to five times inside one variation. Despite it has no transposition table, additive 32-bit Zobrist keys are used to detect repetitions. After first playing the principal variation from the previous iteration, move ordering is improved by the killer heuristic and MVV-LVA for captures. To compare the quality of move ordering, a beta-cutoff ratio L1/L2 >= 1.0 (the smaller, the better) is determined as follows:
Evaluation
The material balance is calculated incrementally and passed as parameter to the recursive alpha-beta routine. Positional considerations, notably piece-square tables including king safety versus king centralization and pawn structure related stuff, are dependent on the game phase, pre-determined at the root before starting the search, that is opening, middle and endgame, separated by the total amount of material on the board.
See also
Publications
- Mariusz Rostek (2008). Program grający w szachy. (Chess playing programs) Engineering Thesis, Technical University of Łódź, advisor Maciej Szmit
Forum Posts
- New winboard engine by Leo Dijksman, Winboard Forum, November 05, 2004
External Links
Chess Engine
Program szachowy Sierzant28 - download Program szachowy Sierżant - Heurystyki
Misc
- Sierżant – Wikipedia.pl (Polish)
References
- ↑ Badge of rank of Sierżant (Sergeant) of the Polish Army, Polish Armed Forces rank insignia - Wikipedia, Wikimedia Commons
- ↑ Mariusz Rostek (2008). Program grający w szachy. (Chess playing programs) Engineering Thesis, Technical University of Łódź, advisor Maciej Szmit
- ↑ Mistrzostwa Polski Programów Szachowych - PGN