getRound(): 0 toString(): Al: single Bob: single Carol: single Diane: single isStable(): false getRound(): 1 toString(): Al: single Bob: engaged to Diane (rank 1) Carol: single Diane: engaged to Bob (rank 1) isStable(): false getRound(): 2 toString(): Al: engaged to Carol (rank 2) Bob: engaged to Diane (rank 1) Carol: engaged to Al (rank 1) Diane: engaged to Bob (rank 1) isStable(): false getRound(): 3 toString(): Al: engaged to Carol (rank 2) Bob: engaged to Diane (rank 1) Carol: engaged to Al (rank 1) Diane: engaged to Bob (rank 1) isStable(): true