Color a Map

color_map:-

map(Name,Regions),

color(Regions),

write(Regions),nl.

color([region(Name,Color,Neibs)|Regions]):-

[Color|Neibs] in 1..4,

outof(Color,Neibs),

indomain(Color),

color(Regions).

color([]).

outof(X,[]).

outof(X,[Y|Ys]):-X #\=Y,outof(X,Ys).