Insight · ★★☆☆☆ · ~5 min
The Dark Room Deck
In the dark, split a deck so both piles have equal face-up cards.
by MindYourPuzzle
You're in a dark room with a shuffled deck of 52 cards. Exactly 10 cards are face-up, the rest face-down. You can't see or feel which is which.
Split the deck into two piles such that each pile has the same number of face-up cards.
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