From ad6b356b20754b7700d46bc4a40b5be24bc95d89 Mon Sep 17 00:00:00 2001
From: Daniel Kukula <daniel.kuku@gmail.com>
Date: Fri, 31 Jul 2026 22:28:43 +0200
Subject: [PATCH 1/2] use tail recursion

---
 lib/elixir/lib/tuple.ex | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/lib/elixir/lib/tuple.ex b/lib/elixir/lib/tuple.ex
index f2da15d6c40..df0e8d12a13 100644
--- a/lib/elixir/lib/tuple.ex
+++ b/lib/elixir/lib/tuple.ex
@@ -132,10 +132,10 @@ defmodule Tuple do
   """
   @doc since: "1.12.0"
   @spec sum(tuple) :: number()
-  def sum(tuple), do: sum(tuple, tuple_size(tuple))
+  def sum(tuple), do: sum(tuple, 1, tuple_size(tuple) + 1, 0)
 
-  defp sum(_tuple, 0), do: 0
-  defp sum(tuple, index), do: :erlang.element(index, tuple) + sum(tuple, index - 1)
+  defp sum(_tuple, top, top, acc), do: acc
+  defp sum(tuple, index, top, acc), do: sum(tuple, index + 1, top, acc + :erlang.element(index, tuple))
 
   @doc """
   Computes a product of tuple elements.
@@ -151,10 +151,12 @@ defmodule Tuple do
   """
   @doc since: "1.12.0"
   @spec product(tuple) :: number()
-  def product(tuple), do: product(tuple, tuple_size(tuple))
+  def product(tuple), do: product(tuple, 1, tuple_size(tuple) + 1, 1)
 
-  defp product(_tuple, 0), do: 1
-  defp product(tuple, index), do: :erlang.element(index, tuple) * product(tuple, index - 1)
+  defp product(_tuple, top, top, acc), do: acc
+
+  defp product(tuple, index, top, acc),
+    do: product(tuple, index + 1, top, acc * :erlang.element(index, tuple))
 
   @doc """
   Converts a tuple to a list.

From 63237ed4367197038ce8d0b957a0754e54548ba1 Mon Sep 17 00:00:00 2001
From: Daniel Kukula <daniel.kuku@gmail.com>
Date: Sat, 1 Aug 2026 07:08:51 +0200
Subject: [PATCH 2/2] format

---
 lib/elixir/lib/tuple.ex | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/elixir/lib/tuple.ex b/lib/elixir/lib/tuple.ex
index df0e8d12a13..273cc79153a 100644
--- a/lib/elixir/lib/tuple.ex
+++ b/lib/elixir/lib/tuple.ex
@@ -135,7 +135,9 @@ defmodule Tuple do
   def sum(tuple), do: sum(tuple, 1, tuple_size(tuple) + 1, 0)
 
   defp sum(_tuple, top, top, acc), do: acc
-  defp sum(tuple, index, top, acc), do: sum(tuple, index + 1, top, acc + :erlang.element(index, tuple))
+
+  defp sum(tuple, index, top, acc),
+    do: sum(tuple, index + 1, top, acc + :erlang.element(index, tuple))
 
   @doc """
   Computes a product of tuple elements.