Shuffle Problem Approach

1. Let a deck be represented by (1 2 3 ... 52).

2. Use integers-from-to to create the deck.

3. Use first-elements-of and list-tail to create the halves (1 2 3 ... 26) and (27 28 29 ... 52).

4. Use a procedure interleave to interleave the two halves:

        (interleave (1 2 3 ... 26)
                    (27 28 29 ... 52)) ⇒ (1 27 2 28 3 29 ... 26 52)
   

5. Check if the result is (1 2 3 ... 52).

6. If not, repeat step 3 on the result.