
crosslist([ [c1,c2], [c2,c1] ]).
joinlist([ [c1,c3] ]).
looplist([ [c3,c3], [c4,c4] ]).
besidelist([ [c1,r1], [c2,r1], [c3,r1], [c3,r2], [c4,r2], [c4,r3] ]).
insidelist([ [c3,r2], [c4,r3] ]).
outsidelist([ [c3,r1], [c4,r2] ]).

