Automating the Test

• Requires eyeballing the resulting deck for orderedness.

• Many shuffles are needlessly repeated from call to call.

Exercise 7.11:

• Write in-order? to test for whether the deck is in order.

• Write shuffle-number to repeatedly shuffle a deck, counting the number of shuffles necessary to get the deck back in order.

            (shuffle-number n) ⇒ number of shuffles required for deck size n
  

  Example:

            (shuffle-number 52) ⇒ ?