2016 Update

Task/Ordered-Partitions/Elixir/ordered-partitions.elixir

@@ -0,0 +1,30 @@
+defmodule Ordered do
+  def partition([]), do: [[]]
+  def partition(mask) do
+    sum = Enum.sum(mask)
+    if sum == 0 do
+      [Enum.map(mask, fn _ -> [] end)]
+    else
+      Enum.to_list(1..sum)
+      |> permute
+      |> Enum.reduce([], fn perm,acc ->
+           {_, part} = Enum.reduce(mask, {perm,[]}, fn num,{pm,a} ->
+             {p, rest} = Enum.split(pm, num)
+             {rest, [Enum.sort(p) | a]}
+           end)
+           [Enum.reverse(part) | acc]
+         end)
+      |> Enum.uniq
+    end
+  end
+
+  defp permute([]), do: [[]]
+  defp permute(list), do: for x <- list, y <- permute(list -- [x]), do: [x|y]
+end
+
+Enum.each([[],[0,0,0],[1,1,1],[2,0,2]], fn test_case ->
+  IO.puts "\npartitions #{inspect test_case}:"
+  Enum.each(Ordered.partition(test_case), fn part ->
+    IO.inspect part
+  end)
+end)