The program smodels is an implementation of the stable model semantics for logic programs. Smodels can be used either as a C++-library that can be called from user programs or as a stand-alone program together with a suitable front-end. The main front-end is lparse.
- Example:
% puzzle1.lp -- Knights and Knaves
% author: Tommi Syrjnen
%
% Raymond Smullyan presents the following puzzle in his book `Forever
% Undecided'.
%
% The Island of Knights and Knaves has two types of inhabitants:
% knights, who always tell the truth, and knaves, who always lie.
%
% One day, three inhabitants (A, B, and C) of the island met a foreign
% tourist and gave the following information about themselves:
%
% 1. A said that B and C are both knights.
% 2. B said that A is a knave and C is a knight.
%
% What types are A, B, and C?
%
% lparse /util/lparse/examples/puzzle/puzzle1.lp | smodels
smodels version 2.34. Reading...done
Answer: 1
Stable Model: knave(a) knave(b) knave(c) person(c) person(b) person(a)
True
Duration: 0.000
Number of choice points: 0
Number of wrong choices: 0
Number of atoms: 20
Number of rules: 28
Number of picked atoms: 1
Number of forced atoms: 1
Number of truth assignments: 23
Size of searchspace (removed): 0 (0)
- Stuart Shapiro, researcher.
- http://www.tcs.hut.fi/Software/smodels/
