81 lines
2.3 KiB
Prolog
81 lines
2.3 KiB
Prolog
%% -*- prolog -*-
|
|
%%=============================================================================
|
|
%% Copyright (C) 2011 by Denys Duchier
|
|
%%
|
|
%% This program is free software: you can redistribute it and/or modify it
|
|
%% under the terms of the GNU Lesser General Public License as published by the
|
|
%% Free Software Foundation, either version 3 of the License, or (at your
|
|
%% option) any later version.
|
|
%%
|
|
%% This program is distributed in the hope that it will be useful, but WITHOUT
|
|
%% ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
%% FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
|
%% more details.
|
|
%%
|
|
%% You should have received a copy of the GNU Lesser General Public License
|
|
%% along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
%%=============================================================================
|
|
|
|
:- use_module(library(gecode)).
|
|
:- use_module(library(maplist)).
|
|
|
|
% 5 people want to have a photograph together, but they have preferences.
|
|
photo(Ex, Solution,Amount) :-
|
|
db(Ex, People, Preferences),
|
|
Space := space,
|
|
length(People, Len),
|
|
Len0 is Len-1,
|
|
People := intvars(Space,Len,0,Len0),
|
|
Space += distinct(People),
|
|
% Bools are the satisfied constraints
|
|
maplist(preferences(Space, Len), Preferences, Bools),
|
|
length(Preferences, PLen),
|
|
Sum := intvar(Space,0,PLen),
|
|
Space += linear(Bools,'IRT_EQ',Sum),
|
|
% add all satisfied constraints
|
|
Space += maximize(Sum),
|
|
Space += branch(People,'INT_VAR_SIZE_MIN','INT_VAL_MIN'),
|
|
SolSpace := search(Space),
|
|
Solution := val(SolSpace,People),
|
|
Amount := val(SolSpace,Sum).
|
|
|
|
%reification, use with care
|
|
preferences(Space, Len, X-Y, B) :-
|
|
NLen is -Len,
|
|
I0 := intvar(Space, NLen, Len),
|
|
I := intvar(Space, 0, Len),
|
|
B := boolvar(Space),
|
|
Space += reify(B, 'RM_EQV', R),
|
|
Space += linear([1,-1],[X,Y],'IRT_EQ', I0),
|
|
Space += abs(I0, I),
|
|
Space += rel(I, 'IRT_EQ', 1, R).
|
|
|
|
|
|
db(s,[Alice,Bob,Carl,Deb,Evan], [Alice-Carl,
|
|
Carl-Deb,
|
|
Deb-Alice,
|
|
Evan-Alice,
|
|
Bob-Evan,
|
|
Carl-Evan,
|
|
Deb-Evan,
|
|
Evan-Bob]).
|
|
|
|
db(l,[Betty,Chris,Donald,Fred,Gary,Mary,Paul,Peter,Susan],
|
|
[Betty-Donald,
|
|
Betty-Gary,
|
|
Betty-Peter,
|
|
Chris-Gary,
|
|
Chris-Susan,
|
|
Donald-Fred,
|
|
Donald-Gary,
|
|
Fred-Betty,
|
|
Fred-Gary,
|
|
Gary-Mary,
|
|
Gary-Betty,
|
|
Mary-Betty,
|
|
Mary-Susan,
|
|
Paul-Donald,
|
|
Paul-Peter,
|
|
Peter-Susan,
|
|
Peter-Paul]).
|