An ‘in shuffle’ is a perfect riffle shuffle on a standard deck of 52 playing cards - that just means a shuffle by splitting the deck in half, then interleaving cards, starting with the top half. Can you write a quick program to solve the following? What is the position of the first card after the 7th shuffle?
How many times must you perform the shuffle so that the top card becomes the bottom card?
When do the first and last cards in the deck touch?
Finally, about how much time did you spend on this problem?