From aae426022145cae83dde43c273ed1ec881c0b18e Mon Sep 17 00:00:00 2001
From: Michael Chu <83269073+michaelCHU95@users.noreply.github.com>
Date: Fri, 28 Jan 2022 11:00:16 +0800
Subject: [PATCH] Recommended Resources for Tree Traversal

Hi, I found these useful pages for in-detail implementation of tree traversal methods (both Iterative and Recursive Approach), especially for beginners.

Preorder (Iterative & Recursive) --> https://www.techiedelight.com/preorder-tree-traversal-iterative-recursive/
Inorder (Iterative & Recursive) --> https://www.techiedelight.com/inorder-tree-traversal-iterative-recursive/
Postorder (Iterative & Recursive) --> https://www.techiedelight.com/postorder-tree-traversal-iterative-recursive/
---
 contents/algorithms/tree.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/contents/algorithms/tree.md b/contents/algorithms/tree.md
index e79493cc..511e3914 100644
--- a/contents/algorithms/tree.md
+++ b/contents/algorithms/tree.md
@@ -38,6 +38,10 @@ Do check out the section on [Trie](trie.md), which is an advanced tree.
 
 In-order traversal of a binary tree is insufficient to uniquely serialize a tree. Pre-order or post-order traversal is also required.
 
+[Pre-order Traversal](https://www.techiedelight.com/preorder-tree-traversal-iterative-recursive/)
+[In-order Traversal](https://www.techiedelight.com/inorder-tree-traversal-iterative-recursive/)
+[Post-order Traversal]( https://www.techiedelight.com/postorder-tree-traversal-iterative-recursive/)
+
 ### Binary Search Tree (BST)
 
 In-order traversal of a BST will give you all elements in order.