/// <summary>
/// Retrieves a chessboard built from the moves performed until the current list top
/// (which may be less than the number of history entries).
/// </summary>
public Board ToChessboard ( )
{
Board board = new Board ( BoardSize ) ;
for ( int i = 0 ; i < ListTop ; i ++ )
board. Move ( List [i]. Line, List [i]. Column ) ;
return ( board ) ;
}