diff --git a/lib/list_ops.ex b/lib/list_ops.ex
index 3010084..eaa75a5 100644
--- a/lib/list_ops.ex
+++ b/lib/list_ops.ex
@@ -1,2 +1,21 @@
 defmodule ListOps do
+  def count([]) do
+    0
+  end
+
+  def count([_head | tail]) do
+    1 + count(tail)
+  end
+
+  def reverse(list) do
+    reverse(list, [])
+  end
+
+  defp reverse([], acumulator) do
+    acumulator
+  end
+
+  defp reverse([head | tail], acumulator) do
+    reverse(tail, [head | acumulator])
+  end
 end
diff --git a/test/list_ops_test.exs b/test/list_ops_test.exs
index c16ecd3..617e680 100644
--- a/test/list_ops_test.exs
+++ b/test/list_ops_test.exs
@@ -39,15 +39,15 @@ defmodule ListOpsTest do
   # end
   #
   # test "filter of empty list" do
-  #   assert ListOps.filter([], &odd?/1) == []
+  #   assert ListOps.filter([], &Integer.is_odd/1) == []
   # end
   #
   # test "filter of normal list" do
-  #   assert ListOps.filter([1,2,3,4], &odd?/1) == [1,3]
+  #   assert ListOps.filter([1,2,3,4], &Integer.is_odd/1) == [1,3]
   # end
   #
   # test "filter of huge list" do
-  #   assert ListOps.filter(Enum.to_list(1..1_000_000), &odd?/1) ==
+  #   assert ListOps.filter(Enum.to_list(1..1_000_000), &Integer.is_odd/1) ==
   #     Enum.map(1..500_000, &(&1*2-1))
   # end
   #