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You'll notice there are the four suits of cards (hearts, diamonds, clubs, and spades). You need to count how many of each suit there are and order them from highest to lowest. Then, match their respective color (black or red) and push the buttons above the door in the corresponding order. If you count spades - 5, diamonds - 4, clubs - 2, hearts - 1, then the buttons above the door would be Black, Red, Black, Red.