From b91738d769119ba8103e4ab4b58f36dbba156290 Mon Sep 17 00:00:00 2001
From: NehaKeshan <39170739+NehaKeshan@users.noreply.github.com>
Date: Tue, 2 Apr 2024 11:09:19 -0400
Subject: [PATCH] Update README.md

---
 lectures/21_trees_IV/README.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lectures/21_trees_IV/README.md b/lectures/21_trees_IV/README.md
index bf7812e..28ed839 100644
--- a/lectures/21_trees_IV/README.md
+++ b/lectures/21_trees_IV/README.md
@@ -20,6 +20,7 @@ red-black tree properties are maintained throughout all
 modifications to the data structure:
 
 - Each node is either red or black.
+- The root node is always black.
 - The NULL child pointers are black.
 - Both children of every red node are black.
 - Thus, the parent of a red node must also be black.