1 % guess matching
   2 match(M,W) :- manAssignsScore(M,_,_), womanAssignsScore(W,_,_), not nonMatch(M,W).
   3 nonMatch(M,W) :- manAssignsScore(M,_,_), womanAssignsScore(W,_,_), not match(M,W).
   4 
   5 % no polygamy
   6 :- match(M1,W), match(M,W), M <> M1.
   7 :- match(M,W), match(M,W1), W <> W1.
   8 
   9 % no singles
  10 jailed(M) :- match(M,_).
  11 :- manAssignsScore(M,_,_), not jailed(M).
  12 
  13 % strong stability condition
  14 :- match(M,W1), manAssignsScore(M,W,Smw), W1 <> W, manAssignsScore(M,W1,Smw1),   Smw >  Smw1,
  15    match(M1,W), womanAssignsScore(W,M,Swm),        womanAssignsScore(W,M1,Swm1), Swm >= Swm1.