CF545A Toy Cars

Little Susie, thanks to her older brother, likes to play with cars. Today she decided to set up a tournament between them. The process of a tournament is described in the next paragraph. There are $ n $ toy cars. Each pair collides. The result of a collision can be one of the following: no car turned over, one car turned over, both cars turned over. A car is good if it turned over in no collision. The results of the collisions are determined by an $ n×n $ matrix $ А $ : there is a number on the intersection of the $ і $ -th row and $ j $ -th column that describes the result of the collision of the $ і $ -th and the $ j $ -th car: - $ -1 $ : if this pair of cars never collided. $ -1 $ occurs only on the main diagonal of the matrix. - $ 0 $ : if no car turned over during the collision. - $ 1 $ : if only the $ i $ -th car turned over during the collision. - $ 2 $ : if only the $ j $ -th car turned over during the collision. - $ 3 $ : if both cars turned over during the collision. Susie wants to find all the good cars. She quickly determined which cars are good. Can you cope with the task?

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