Although Blackjack is a game of chance, it is simple enough that the mathematically optimal next move can be given for any hand. This stores the set of optimal moves for a 1 deck blackjack hand, asking the user for his or her current hand (and the dealer's up card), then gives the user his or her optimal move.

The prompts to the user look something like this:

Please enter your first card:

(user enters 9)

Please enter your second card:

(user enters 9)

Please enter the dealer's card:

(user enters 7)

Your optimal move is to stand.

You can either allow the user to enter J, Q, or K for Jack, Queen, or King, respectively, or you can expect the user to enter a 10 for any of these. However, the user should have to enter A for an Ace.