Germann and Chekalinshy laid out 13 different cards on the table. Each card can lie in one of two positions: face up or face down. The players must take turns flipping one card at a time. The player who, after their move, repeats any previous situation (including the initial one) loses. Chekalinshy made the first move. Who can win regardless of how the opponent plays?
Chakalinsky's winning strategy is to flip the same card every time (for example, the Queen of Spades). All possible positions can be divided into pairs that differ only in the location of the Queen of Spades. If, in response to Chakalinsky's move, Hermann also flips the Queen of Spades, the previous position will be repeated, and he will lose. Therefore, he is forced to flip another card. And by flipping the Queen of Spades in response, Chakalinsky will get a position that is paired with the one that just was. Thus, with each move, Hermann will have to "start" a new pair, and Chakalinsky will always be able to make a response move, "finishing" the pair. Since the number of possible positions is finite, sooner or later Hermann will not be able to open a new pair and will lose.

## Answer

Chakalinsky.

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