% File 'example2': Coloring a graph.
% Copy dlv from directory /projects/tag/dlv/current/sun/ .
% Command line: 'dlv -silent -n=1 -N=5 example2'
% or: 'dlv -silent -n=1 -N=5 -filter=color example2'.

node(X) :- #int(X).

edge(0,1).
edge(0,2). 
edge(1,2).
edge(1,3).
edge(2,4).
edge(3,4).
edge(3,5).
edge(4,5).

color(X,r) ; color(X,b) ; color(X,g) :- node(X).

:- edge(X,Y), color(X,C), color(Y,C).