Mix.install([
{:jason, "~> 1.4"},
{:kino, "~> 0.9", override: true},
{:youtube, github: "brooklinjazz/youtube"},
{:hidden_cell, github: "brooklinjazz/hidden_cell"}
])
We're going to build some logic for a card counting application. Card counting is a strategy used in card games to determine if there are more high cards or low cards in the deck.
There are 13 numbered cards in a common deck of playing cards.
We'll use integers 1
to 13
to represent playing cards. Cards are either low, normal, or high.
flowchart LR
subgraph low cards
direction LR
1 --- 2 --- 3 --- 4 --- 5 --- 6
end
subgraph Normal Cards
direction LR
7 --- 8 --- 9
end
subgraph High Cards
direction LR
10 --- 11 --- 12 --- 13
end
In order to track if there are more high cards left in the deck, or low cards left in the deck, you'll track a running count starting at 0
.
- When dealt a low card decrease the count by
1
. - When dealt a high card increase the count by
1
. - When dealt a normal card do nothing.
Bind integers low
, normal
, and high
to track the amount to increase or decrease the current count by. You will use these variables in further exercises.
Example solution
low = -1
normal = 0
high = 1
Enter your solution below.
The initial count is 0
. You have been dealt one high card. Use arithmetic operators and the bound variables above to determine the new count.
Example solution
initial_count = 0
initial_count + high
Enter your solution below.
The initial count is 0
. You have been dealt one low card. Use arithmetic operators and the bound variables above to determine the new count.
Example solution
initial_count = 0
initial_count + low
Enter your solution below.
The initial count is 5
. You have been dealt five high cards, two low cards, and two normal cards. Use arithmetic operators and the bound variables above to determine the new count.
Example solution
initial_count = 5
initial_count + high * 5 + low * 2 + normal * 2
You could omit the normal cards or allow high and low cards to balance each other, however if the increment/decrement value changes then your code would break.
Enter your solution below.
You are dealt three cards of a random value between 1
and 13
. You can use Enum.random/1 to generate a random number.
random_card = Enum.random(1..13)
Generate three random cards, use the values of the three randomly generated cards to determine the current count given the initial count is 0
.
Example solution
random_card1 = Enum.random(1..13)
random_card2 = Enum.random(1..13)
random_card3 = Enum.random(1..13)
cards =
Enum.map([random_card1, random_card2, random_card3], fn random_card ->
cond do
random_card <= 6 -> low
random_card >= 10 -> high
true -> normal
end
end)
Enum.sum(cards)
You could omit the normal cards or allow high and low cards to balance each other, however if the increment/decrement value changes then your code would break.
Enter your solution below.
DockYard Academy now recommends you use the latest Release rather than forking or cloning our repository.
Run git status
to ensure there are no undesirable changes.
Then run the following in your command line from the curriculum
folder to commit your progress.
$ git add .
$ git commit -m "finish Card Counting exercise"
$ git push
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We also offer a paid course where you can learn from an instructor alongside a cohort of your peers. We will accept applications for the June-August 2023 cohort soon.