Data commit

Task/Knuth-shuffle/Elixir/knuth-shuffle.elixir

@@ -0,0 +1,22 @@
+defmodule Knuth do
+  def shuffle( inputs ) do
+    n = length( inputs )
+    {[], acc} = Enum.reduce( n..1, {inputs, []}, &random_move/2 )
+    acc
+  end
+
+  defp random_move( n, {inputs, acc} ) do
+    item = Enum.at( inputs, :rand.uniform(n)-1 )
+    {List.delete( inputs, item ), [item | acc]}
+  end
+end
+
+seq = Enum.to_list( 0..19 )
+IO.inspect Knuth.shuffle( seq )
+
+seq = [1,2,3]
+Enum.reduce(1..100000, Map.new, fn _,acc ->
+  k = Knuth.shuffle(seq)
+  Map.update(acc, k, 1, &(&1+1))
+end)
+|> Enum.each(fn {k,v} -> IO.inspect {k,v} end)