crypto_square started

elixir/crypto-square/lib/crypto_square.ex

@@ -0,0 +1,31 @@
+defmodule CryptoSquare do
+  @doc """
+  Encode string square methods
+  ## Examples
+
+    iex> CryptoSquare.encode("abcd")
+    "ac bd"
+  """
+  @spec encode(String.t()) :: String.t()
+  def encode(str) do
+    str
+    |> normalize()
+    |> square()
+  end
+
+  defp normalize(str) do
+    str
+    |> String.downcase()
+    |> String.replace(~r/[^a-z0-9]/, "")
+  end
+
+  defp square(str) do
+    length = String.length(str)
+    row = :math.ceil(length ** 0.5)
+    col = :math.ceil(length / row)
+
+    str
+    |> String.split("", trim: true)
+    |> Enum.chunk_every(col, col)
+  end
+end