Retrieve a message in a deck of cards!
There are 52! unique ways to put 52 playing cards in order. By establishing a mathematical correspondence between an order of letters and the order of cards, we can hide a message in the deck of cards by simply putting them in the correct order. Read a full explanation, play with the encoding demo, or the decoding demo below.
I used the free javascript BigInt library to do large-number calculations.
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