%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1996-2010. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%% http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% %CopyrightEnd%
%%
%%
-module(othello_adt).
-compile(export_all).
%%-------------------------------------------------------
%% Use three main states for the strategy:
%%
%% BeginPlay: Stay in the inner square as long as possible.
%% Use the possible_draws/3.
%%
%% MiddlePlay: Try to choose stable markers (?)
%% Use stable/3
%%
%% EndPlay: Try to flip as many markers as possible
%%
%% The transition from Begin to Middle is obvious. From Middle
%% to End however, is can be discussed.
%%-------------------------------------------------------
test(N,B) ->
X=new(B),
statistics(wall_clock),
test0(N,X),
{_,T} = statistics(wall_clock),
{time_was,T/N}.
test0(0,_) -> true;
test0(N,X) ->
possible_draws(black,X,begin_play),
test0(N-1,X).
%%-------------------------------------------------------
%% new/1 - returns a new board
%%
%% Uses a tuple for storing the board
%%-------------------------------------------------------
new(B) ->
Board = mk_board(B),
{ordsets:from_list([18,19,20,21,26,29,34,37,42,43,44,45]),Board}.
mk_board(t) ->
Tup = list_to_tuple(gen_list(64,grey)),
Tup1 = setelement(28+1, Tup, white),
Tup2 = setelement(35+1, Tup1, white),
Tup3 = setelement(27+1, Tup2, black),
gen_score_board(),
setelement(36+1, Tup3, black).
gen_list(0,_) -> [];
gen_list(I,Def) -> [Def|gen_list(I-1,Def)].
gen_score_board() -> put(score,list_to_tuple(gen_list(64,0))).
%%-------------------------------------------------------
%% pos(Col,Row) - returns a position describing column
%% and row.
%% Col and Row have the range 1 - 8.
%%-------------------------------------------------------
pos(Col,Row) -> ((Row - 1) bsl 3) + (Col - 1).
%%-------------------------------------------------------
%% col(Pos) - returns the column of the Pos position
%%-------------------------------------------------------
col(Pos) -> (Pos band 7) + 1.
%%-------------------------------------------------------
%% row(Pos) - returns the row of the Pos position
%%-------------------------------------------------------
row(Pos) -> (Pos bsr 3) + 1.
%%-------------------------------------------------------
%% is_draw(Pos,Colour,Board) - returns true if Pos is a
%% correct draw.
%%-------------------------------------------------------
is_draw(Pos,Colour,{Bset,Board}) ->
case ordsets:is_element(Pos,Bset) of
true ->
case catch is_good(Colour,Pos,Board) of
true ->
true;
_ ->
false
end;
_ ->
false
end.
%%-------------------------------------------------------
%% set(Pos,Colour,Board) - returns an updated board
%%-------------------------------------------------------
set(Pos,Colour,{Bset,Board}) ->
case ordsets:is_element(Pos,Bset) of
true ->
NewBoard = setelement(Pos+1,Board,Colour),
Empty = empty_neighbour(Pos,NewBoard),
NewBset = ordsets:union(Empty,ordsets:del_element(Pos,Bset)),
turn(Colour,Pos,{NewBset,NewBoard});
_ ->
{error,invalid_position}
end.
empty_neighbour(Pos,Board) ->
ordsets:from_list(empty_neighbour(Pos,Board,deltas())).
empty_neighbour(_,_,[]) -> [];
empty_neighbour(Pos,Board,[H|T]) ->
case is_empty(Pos+H,dir(Pos,H),Board) of
true -> [Pos+H|empty_neighbour(Pos,Board,T)];
_ -> empty_neighbour(Pos,Board,T)
end.
is_empty(_,false,_) -> false;
is_empty(X,_,_Board) when X<0 -> false;
is_empty(X,_,_Board) when X>63 -> false;
is_empty(X,_,Board) ->
case element(X+1,Board) of
grey -> true; % Empty
_ -> false
end.
%%-------------------------------------------------------
%% get(Pos,Board) - returns the contents in Pos
%%-------------------------------------------------------
get(Pos,{_Bset,Board}) -> element(Pos+1,Board).
%%-------------------------------------------------------
%% pieces(Colour,Board) - returns the number of Colour
%% pieces.
%%-------------------------------------------------------
pieces(Colour,{_Bset,Board}) ->
pieces(Colour,Board,0,0).
pieces(Colour,Board,Pos,Count) when Pos < 64 ->
case element(Pos+1,Board) of
Colour ->
pieces(Colour,Board,Pos+1,Count+1);
_ ->
pieces(Colour,Board,Pos+1,Count)
end;
pieces(_,_,_,Count) ->
Count.
%%-------------------------------------------------------
%% possible_draws(Colour, Board, State)
%%
%% Returns a list of possible draws regarding the current
%% strategy state.
%%-------------------------------------------------------
possible_draws(Colour,{Bset,Board},begin_play) ->
Dset = ordsets:intersection(Bset,inner_square()),
possible_draws_0(Colour,Dset,Board);
possible_draws(Colour,{Bset,Board},_) ->
possible_draws_0(Colour,Bset,Board).
possible_draws(Colour,{Bset,Board}) ->
possible_draws_0(Colour,Bset,Board).
possible_draws_0(_,[],_) -> [];
possible_draws_0(Colour,[H|T],Board) ->
case catch is_good(Colour,H,Board) of
true -> [H|possible_draws_0(Colour,T,Board)];
false -> possible_draws_0(Colour,T,Board)
end.
%%-------------------------------------------------------
%% evaluate_board(Colour,Board) - returns the value of
%% the board from Colours
%% point of view.
%%-------------------------------------------------------
evaluate_board(Colour,{_Bset,Board}) ->
Score = get(score), % Initialized (zeroed) score board !!
Colour1 = swap(Colour),
Score1 = eval_board(Colour,Colour1,Score,Board,0),
Score2 = cnt_corner(0,Score1,Board,Colour,Colour1),
Score3 = cnt_corner(7,Score2,Board,Colour,Colour1),
Score4 = cnt_corner(56,Score3,Board,Colour,Colour1),
Score5 = cnt_corner(63,Score4,Board,Colour,Colour1),
count(Score5,0).
% A = count(Score5,0),
% io:format('Score = ~w~n',[A]),
% A.
eval_board(MyCol,OtCol,Score,Board,Pos) when Pos < 64 ->
case element(Pos+1,Board) of
MyCol ->
Score1 = setelement(Pos+1,Score,score(Pos)),
eval_board(MyCol,OtCol,Score1,Board,Pos+1);
OtCol ->
Score1 = setelement(Pos+1,Score,-score(Pos)),
eval_board(MyCol,OtCol,Score1,Board,Pos+1);
_ ->
eval_board(MyCol,OtCol,Score,Board,Pos+1)
end;
eval_board(_,_,Score,_,_) ->
Score.
cnt_corner(Corner,Score,Board,MyCol,OtCol) ->
case element(Corner+1,Board) of
MyCol ->
cnt_corn(Corner,setelement(Corner+1,Score,50),
Board,50,MyCol);
OtCol ->
cnt_corn(Corner,setelement(Corner+1,Score,-50),
Board,-50,OtCol);
_ ->
Score
end.
cnt_corn(0,Score,Board,Value,Colour) ->
Score1 = cnt_corn(0,1,8,Score,Board,Value,Colour),
cnt_corn(0,8,1,Score1,Board,Value,Colour);
cnt_corn(7,Score,Board,Value,Colour) ->
Score1 = cnt_corn(7,-1,8,Score,Board,Value,Colour),
cnt_corn(7,8,-1,Score1,Board,Value,Colour);
cnt_corn(56,Score,Board,Value,Colour) ->
Score1 = cnt_corn(56,1,-8,Score,Board,Value,Colour),
cnt_corn(56,-8,1,Score1,Board,Value,Colour);
cnt_corn(63,Score,Board,Value,Colour) ->
Score1 = cnt_corn(63,-1,-8,Score,Board,Value,Colour),
cnt_corn(63,-8,-1,Score1,Board,Value,Colour).
cnt_corn(Pos,Dir,LineDir,Score,Board,Value,Colour) ->
case dir(Pos,Dir) of
Dir ->
NextEdge = Pos+Dir,
case element(NextEdge+1,Board) of
Colour ->
Score1 = setelement(NextEdge+1,Score,Value),
Score2 = cnt_line(NextEdge,LineDir,Score1,Board,
Colour,Value),
cnt_corn(NextEdge,Dir,LineDir,Score2,Board,Value,Colour);
_ ->
Score
end;
_ ->
Score
end.
cnt_line(Pos,Dir,Score,Board,Colour,Value) ->
case dir(Pos,Dir) of
Dir ->
OnLinePos = Pos+Dir,
case element(OnLinePos+1,Board) of
Colour ->
Score1 = setelement(OnLinePos+1,Score,Value),
cnt_line(OnLinePos,Dir,Score1,Board,Colour,Value);
_ ->
Score
end;
_ ->
Score
end.
count(Score,Pos) when Pos < 64 ->
element(Pos+1,Score) + count(Score,Pos+1);
count(_,_) ->
0.
swap(white) -> black;
swap(black) -> white.
%%-------------------------------------------------------
%% stable(Colour,Pos,Board) - returns a value 0-8
%%
%% A high value is regarded as more stable than a lower one.
%% The stability means how many "friendly" neighbours there
%% are, i.e markers of the same colour. Neighbours positions
%% outside the board are regarded as friendly.
%%-------------------------------------------------------
stable(Colour,Pos,{_,Board}) ->
stable(deltas(),Colour,Pos,Board).
stable([],_,_,_) -> 0;
stable([H|T],Colour,Pos,Board) ->
stable_val(Colour,Pos,H,Board) + stable(T,Colour,Pos,Board).
stable_val(_,H,D,_) when H+D<0 -> 1;
stable_val(_,H,D,_) when H+D>63 -> 1;
stable_val(black,H,D,Board) ->
case element((H+D)+1,Board) of
black -> 1;
_ -> 0
end;
stable_val(white,H,D,Board) ->
case element((H+D)+1,Board) of
white -> 1;
_ -> 0
end.
%%-------------------------------------------------------
%% diff(Board,OldBoard) - return a list of the positions
%% with changed pieces.
%% [{Pos1,Colour1},...]
%%-------------------------------------------------------
diff(Board,OldBoard) -> diff(0,Board,OldBoard).
diff(Pos,Board,OldBoard) when Pos < 64 ->
OldP = get(Pos,OldBoard),
case get(Pos,Board) of
OldP ->
diff(Pos+1,Board,OldBoard);
NewP ->
[{Pos,NewP}|diff(Pos+1,Board,OldBoard)]
end;
diff(_,_,_) ->
[].
%%-------------------------------------------------------
%% all_pos(Board) - return a list of the positions colour.
%% [{Pos1,Colour1},...]
%%-------------------------------------------------------
all_pos(Board) -> all_pos(0,Board).
all_pos(Pos,Board) when Pos < 64 ->
[{Pos,get(Pos,Board)}|all_pos(Pos+1,Board)];
all_pos(_,_) ->
[].
%%-------------------------------------------------------
%% Internal stuff
%%-------------------------------------------------------
deltas() -> [9,8,7,1,-1,-7,-8,-9].
inner_square() ->
[18,19,20,21,26,27,28,29,34,35,36,37,42,43,44,45]. % Is already an ordset
% Save list traversing.
% ordsets:list_to_set([18,19,20,21,26,27,28,29,34,35,36,37,42,43,44,45]).
inv(black) -> white;
inv(white) -> black.
is_good(Colour,H,Board) ->
is_good_0(Colour,H,dir(H,-9),Board),
is_good_0(Colour,H,dir(H,-8),Board),
is_good_0(Colour,H,dir(H,-7),Board),
is_good_0(Colour,H,dir(H,-1),Board),
is_good_0(Colour,H,dir(H,1),Board),
is_good_0(Colour,H,dir(H,7),Board),
is_good_0(Colour,H,dir(H,8),Board),
is_good_0(Colour,H,dir(H,9),Board),
false.
is_good_0(_,_,false,_) -> false;
is_good_0(_,H,D,_) when is_integer(H), is_integer(D), H+D<0 -> false;
is_good_0(_,H,D,_) when is_integer(H), is_integer(D), H+D>63 -> false;
is_good_0(black,H,D,Board) when is_integer(H), is_integer(D) ->
case element((H+D)+1,Board) of
white -> is_good_1(black,H+D,dir(H+D,D),Board);
_ -> false
end;
is_good_0(white,H,D,Board) when is_integer(H), is_integer(D) ->
case element((H+D)+1,Board) of
black -> is_good_1(white,H+D,dir(H+D,D),Board);
_ -> false
end.
is_good_1(_,_,false,_) -> false;
is_good_1(_,H,D,_) when is_integer(H), is_integer(D), H+D<0 -> false;
is_good_1(_,H,D,_) when is_integer(H), is_integer(D), H+D>63 -> false;
is_good_1(black,H,D,Board) when is_integer(H), is_integer(D) ->
case element((H+D)+1,Board) of
white -> is_good_1(black,H+D,dir(H+D,D),Board);
black -> throw(true);
_ -> false
end;
is_good_1(white,H,D,Board) when is_integer(H), is_integer(D) ->
case element((H+D)+1,Board) of
black -> is_good_1(white,H+D,dir(H+D,D),Board);
white -> throw(true);
_ -> false
end.
%%-------------------------------------------------------
%% turn(Colour,Draw,Board) - returns an updated board
%% turn all possible pieces
%% on the board
%% Neighbours are not changed !!
%%-------------------------------------------------------
turn(Colour,Draw,{Bset,Board}) ->
{Bset,turn(Colour,Draw,-9,
turn(Colour,Draw,-8,
turn(Colour,Draw,-7,
turn(Colour,Draw,-1,
turn(Colour,Draw,1,
turn(Colour,Draw,7,
turn(Colour,Draw,8,
turn(Colour,Draw,9,Board))))))))}.
turn(Colour,H,D,Board) ->
case catch is_good_0(Colour,H,dir(H,D),Board) of
true ->
turn_0(Colour,H,D,Board);
false ->
Board
end.
turn_0(_,H,D,B) when is_integer(H), is_integer(D), H+D<0 -> B;
turn_0(_,H,D,B) when is_integer(H), is_integer(D), H+D>63 -> B;
turn_0(black,H,D,Board) when is_integer(H), is_integer(D) ->
E = H+D,
case element(E+1,Board) of
white -> turn_0(black,H+D,D,swap(black,E,Board));
_ -> Board
end;
turn_0(white,H,D,Board) when is_integer(H), is_integer(D) ->
E = H+D,
case element(E+1,Board) of
black -> turn_0(white,H+D,D,swap(white,E,Board));
_ -> Board
end.
%%-------------------------------------------------------
%% swap(Colour,Pos,Board) - returns an updated board
%% turn a piece on the board
%% Neighbours are not changed !!
%%-------------------------------------------------------
swap(Colour,Pos,Board) when is_integer(Pos) ->
setelement(Pos+1,Board,Colour).
score(Pos) -> score1({col(Pos),row(Pos)}).
score1({Column,1}) when Column >= 3, Column =< 6 -> 20;
score1({Column,8}) when Column >= 3, Column =< 6 -> 20;
score1({1,Line}) when Line >= 3, Line =< 6 -> 20;
score1({8,Line}) when Line >= 3, Line =< 6 -> 20;
score1({Column,2}) when Column >= 3, Column =< 6 -> -7;
score1({Column,7}) when Column >= 3, Column =< 6 -> -7;
score1({2,Line}) when Line >= 3, Line =< 6 -> -7;
score1({7,Line}) when Line >= 3, Line =< 6 -> -7;
score1({Column,Line}) when Column >= 3, Column =< 6,
Line >= 3, Line =< 6 -> 1;
score1({1,1}) -> 100;
score1({1,8}) -> 100;
score1({8,1}) -> 100;
score1({8,8}) -> 100;
score1({2,1}) -> -30;
score1({7,1}) -> -30;
score1({1,2}) -> -30;
score1({8,2}) -> -30;
score1({1,7}) -> -30;
score1({8,7}) -> -30;
score1({2,8}) -> -30;
score1({7,8}) -> -30;
score1({2,2}) -> -50;
score1({7,2}) -> -50;
score1({2,7}) -> -50;
score1({7,7}) -> -50.
%%-------------------------------------------------------
%% dir(Pos,Dir) - return Dir if allowed direction at Pos.
%% else return false.
%%-------------------------------------------------------
dir(0,1) -> 1; % {1,1}
dir(0,8) -> 8;
dir(0,9) -> 9;
dir(0,_) -> false;
dir(7,-1) -> -1; % {8,1}
dir(7,7) -> 7;
dir(7,8) -> 8;
dir(7,_) -> false;
dir(56,-8) -> -8; % {1,8}
dir(56,-7) -> -7;
dir(56,1) -> 1;
dir(56,_) -> false;
dir(63,-9) -> -9; % {8,8}
dir(63,-8) -> -8;
dir(63,-1) -> -1;
dir(63,_) -> false;
dir(Pos,-1) when (Pos bsr 3) == 0 -> -1; % {_,1}
dir(Pos,1) when (Pos bsr 3) == 0 -> 1;
dir(Pos,7) when (Pos bsr 3) == 0 -> 7;
dir(Pos,8) when (Pos bsr 3) == 0 -> 8;
dir(Pos,9) when (Pos bsr 3) == 0 -> 9;
dir(Pos,_) when (Pos bsr 3) == 0 -> false;
dir(Pos,-9) when (Pos bsr 3) == 7 -> -9; % {_,8}
dir(Pos,-8) when (Pos bsr 3) == 7 -> -8;
dir(Pos,-7) when (Pos bsr 3) == 7 -> -7;
dir(Pos,-1) when (Pos bsr 3) == 7 -> -1;
dir(Pos,1) when (Pos bsr 3) == 7 -> 1;
dir(Pos,_) when (Pos bsr 3) == 7 -> false;
dir(Pos,-8) when (Pos band 7) == 0 -> -8; % {1,_}
dir(Pos,-7) when (Pos band 7) == 0 -> -7;
dir(Pos,1) when (Pos band 7) == 0 -> 1;
dir(Pos,8) when (Pos band 7) == 0 -> 8;
dir(Pos,9) when (Pos band 7) == 0 -> 9;
dir(Pos,_) when (Pos band 7) == 0 -> false;
dir(Pos,-9) when (Pos band 7) == 7 -> -9; % {8,_}
dir(Pos,-8) when (Pos band 7) == 7 -> -8;
dir(Pos,-1) when (Pos band 7) == 7 -> -1;
dir(Pos,7) when (Pos band 7) == 7 -> 7;
dir(Pos,8) when (Pos band 7) == 7 -> 8;
dir(Pos,_) when (Pos band 7) == 7 -> false;
dir(_Pos,Dir) -> Dir.
