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Play Your Cards!
Play Your Cards!

Play Your Cards!

Learning Exercise

While completing Play Your Cards!, you'll learn 1 concept

Instructions

In this exercise we will simulate the first turn of a Blackjack game.

You will receive two cards and will be able to see the face up card of the dealer. All cards are represented using a string such as "ace", "king", "three", "two", etc. The values of each card are:

card value card value
ace 11 eight 8
two 2 nine 9
three 3 ten 10
four 4 jack 10
five 5 queen 10
six 6 king 10
seven 7 other 0

Note: Commonly, aces can take the value of 1 or 11 but for simplicity we will assume that they can only take the value of 11.

Depending on your two cards and the card of the dealer, there is a strategy for the first turn of the game, in which you have the following options:

- Stand (S)
- Hit (H)
- Split (P)
- Automatically win (W)

Although not optimal yet, you will follow the strategy your friend Alex has been developing, which is as follows:

Category: Large Hand

  • If you have a pair of aces you must always split them.
  • If you have a Blackjack (two cards that sum up to a value of 21), and the dealer does not have an ace, a figure or a ten then you automatically win. If the dealer does have any of those cards then you'll have to stand and wait for the reveal of the other card.

Category: Small Hand

  • If your cards sum up to 17 or higher you should always stand.
  • If your cards sum up to 11 or lower you should always hit.
  • If your cards sum up to a value within the range [12, 16] you should always stand unless the dealer has a 7 or higher, in which case you should always hit.

The overall logic has already been implemented. You have four tasks:

1. Calculate the score of any given card.

Implement a function to calculate the numerical value of a card given its name using conditionals.

parseCard("ace")
// returns 11

2. Determine if two cards make up a Blackjack.

Implement a function that returns true if two cards form a Blackjack, false otherwise.

isBlackjack("queen", "ace")
// returns true

3. Implement the decision logic for hand scores larger than 20 points.

Implement a function that returns the string representation of a decision given your cards. This function is only called if the handScore is larger than 20. It will receive 2 arguments: isBlackJack and dealerScore. It should implement the bulletpoints in the category "Large Hand" above.

isBlackJack = true
dealerScore = 7
largeHand(isBlackJack, dealerScore)
// returns "W"

4. Implement the decision logic for hand scores with less than 21 points.

Implement a function that returns the string representation of a decision given your cards. This function is only called if the handScore is less than 21. It will receive 2 arguments: handScore and dealerScore. It should implement the bulletpoints in the category "Small Hand" above.

handScore = 15
dealerScore = 12
SmallHand(handScore, dealerScore)
// returns "H"
Last updated 30 June 2022
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