Task two is done

Author: jamiecurle

w1/mini_max_sum.ex

@@ -0,0 +1,34 @@
+defmodule  Hackerrank.W1.MiniMaxSum do
+  @moduledoc """
+  Mini Max Sum – Challenge 2 – Week 1
+  <https://www.hackerrank.com/challenges/three-month-preparation-kit-mini-max-sum/problem>
+  """
+
+  @doc """
+  Calculates the minimum and maximum values obtainable by summing exactly
+  four of five integers. Optionally prints the result as space-separated values.
+
+  ## Parameters
+    - `arr`: a list of integers
+
+  ## Returns
+    - a list with two integers: `[min_sum, max_sum]`
+
+  ## Examples
+
+      iex> mini_max_sum([1, 2, 3, 4, 5])
+      [10, 14]
+  """
+  @spec challenge([integer()]) :: [integer()]
+  def challenge(arr) do
+    # sort the array
+    arr = Enum.sort(arr)
+
+    # slice the mins and sum
+    [
+      Enum.take(arr, 4) |> Enum.sum(),
+      Enum.drop(arr, 1) |> Enum.sum()
+    ]
+  end
+
+end

w1/mini_max_sum_test.exs

@@ -0,0 +1,35 @@
+defmodule Hackerank.W1.MiniMaxSumTests do
+
+  use ExUnit.Case
+  alias Hackerrank.Test.Helper
+  alias Hackerrank.W1.MiniMaxSum
+
+  @pattern "w1/tc/2_*.txt"
+
+  test "run the tests" do
+    Helper.test_all(@pattern, &parse_args/1, &parse_expected/1 )
+    |> Enum.each(fn [args, expected] ->
+      assert MiniMaxSum.challenge(args) == expected
+    end)
+  end
+
+  def parse_args(raw) do
+    # get the data out of a list
+    [raw] = raw
+
+    # now split it
+    String.split(raw, " ")
+    |> Enum.map(&String.to_integer/1)
+  end
+
+  def parse_expected(raw) do
+    # in this challange the raw data is already correct - a list of floaty-strings
+    # get the data out of a list
+    [raw] = raw
+
+    # now split it
+    String.split(raw, " ")
+    |> Enum.map(&String.to_integer/1)
+  end
+
+end