Create README - LeetHub

Author: JanaSabuj

binary-tree-zigzag-level-order-traversal/README.md

@@ -0,0 +1,29 @@
+<h2>103. Binary Tree Zigzag Level Order Traversal</h2><h3>Medium</h3><hr><div><p>Given the <code>root</code> of a binary tree, return <em>the zigzag level order traversal of its nodes' values</em>. (i.e., from left to right, then right to left for the next level and alternate between).</p>
+
+<p>&nbsp;</p>
+<p><strong>Example 1:</strong></p>
+<img alt="" src="https://assets.leetcode.com/uploads/2021/02/19/tree1.jpg" style="width: 277px; height: 302px;">
+<pre><strong>Input:</strong> root = [3,9,20,null,null,15,7]
+<strong>Output:</strong> [[3],[20,9],[15,7]]
+</pre>
+
+<p><strong>Example 2:</strong></p>
+
+<pre><strong>Input:</strong> root = [1]
+<strong>Output:</strong> [[1]]
+</pre>
+
+<p><strong>Example 3:</strong></p>
+
+<pre><strong>Input:</strong> root = []
+<strong>Output:</strong> []
+</pre>
+
+<p>&nbsp;</p>
+<p><strong>Constraints:</strong></p>
+
+<ul>
+	<li>The number of nodes in the tree is in the range <code>[0, 2000]</code>.</li>
+	<li><code>-100 &lt;= Node.val &lt;= 100</code></li>
+</ul>
+</div>