Change string category to atom

Co-authored-by: Angelika Tyborska <[email protected]>

Author: elibdev

exercises/practice/yacht/lib/yacht.ex

@@ -1,8 +1,21 @@
 defmodule Yacht do
+  @type category ::
+          :ones
+          | :twos
+          | :threes
+          | :fours
+          | :fives
+          | :sixes
+          | :full_house
+          | :four_of_a_kind
+          | :little_straight
+          | :big_straight
+          | :choice
+          | :yacht
+
   @doc """
   Calculate the score of 5 dice using the given category's scoring method.
   """
-  @spec score(category :: String.t(), dice :: [integer]) :: integer
-  def score(category, dice) do
+  @spec score(category :: category(), dice :: [integer]) :: integer
   end
 end