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Alice in Wonderland [1]

an experimental open source chess engine under the GNU General Public License by Sven Reichard, written in C++ and compliant with the Chess Engine Communication Protocol. Alice is an object oriented program developed under GCC and Linux. The board is a vector of 64 pointers to pieces, while piece is an abstract class, with intermediate subclasses for common piece properties such as sliding versus none sliding pieces, and finally instantiable subclasses for the concrete pieces, like pawn, rook, etc., and "null pieces" for the empty squares [2]. Jim Ablett provides compiles for 32/64-bit Windows and Linux [3].


Alice is an object oriented Bitboard engine, applying Rotated Bitboards to determine sliding piece attacks. Size of of the encapsulated Bitboard class is 8 by unsigned long long number [4].

namespace Alice
  class BitboardIterator;
  class Bitboard
    typedef BitboardIterator Iterator;
    Bitboard( unsigned long long n = 0ull);
    //operator unsigned long long() const;
    Bitboard& operator|=( const Bitboard& b );
    Bitboard& operator&=( const Bitboard& b );
    Bitboard operator~( ) const;
    unsigned long long number;
    static std::vector<unsigned long long> setMask;
    static std::vector<unsigned long long> clearMask;
    static Bitboard fileAttacks[256][64];
    static Bitboard rankAttacks[256][64] ;
    static Bitboard upDiagonalAttacks[256][64];
    static Bitboard downDiagonalAttacks[256][64] ;

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External Links

Chess Engine


Alice chess game.png


  1. Jessie Willcox Smith's illustration of Alice surrounded by the characters of Wonderland. (1923), Alice's Adventures in Wonderland from Wikipedia
  2. Re: Gestatten: Alice by Sven Reichard, CCC, June 25, 2002
  3. Index of /chess/engines/Jim Ablett/ALICE by Jim Ablett, hosted by Kirill Kryukov
  4. Index of /chess/engines/Jim Ablett/ALICE by Jim Ablett, hosted by Kirill Kryukov, Src/include/Bitboard.h
  5. Lewis Carroll's diagram of the story as a chess game, Through the Looking-Glass - Chess
  6. Glen Robert Downey (1998). The Truth About Pawn Promotion: The Development of the Chess Motif in Victorian Fiction. Ph.D. thesis, University of Victoria pdf » Promotions
  7. Lewis Carroll's chess problem | ChessVibes, July 14, 2008

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