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Difficulty: Easy/Rotate by 90 degree/README.md

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+<h2><a href="https://www.geeksforgeeks.org/problems/rotate-by-90-degree-1587115621/1">Rotate by 90 degree</a></h2><h3>Difficulty Level : Difficulty: Easy</h3><hr><div class="problems_problem_content__Xm_eO"><p><span style="font-size: 18px;">Given a<strong> </strong>square<strong> </strong>matrix <strong>mat</strong>[][] of size <strong>n x n</strong>. The task is to rotate it by<strong> 90 degrees</strong> in an<strong> anti-clockwise</strong> direction without using any extra space.&nbsp;</span><br><br><span style="font-size: 18px;"><strong>Examples:</strong></span></p>
+<pre><span style="font-size: 18px;"><strong>Input</strong>: mat[][] = [[1, 2, 3],
+&nbsp;               [4, 5, 6]
+&nbsp;               [7, 8, 9]]
+<strong>Output</strong>: Rotated Matrix:
+[3, 6, 9]
+[2, 5, 8]
+[1, 4, 7]
+</span></pre>
+<pre><span style="font-size: 18px;"><strong>Input</strong>: mat[][] = [[1, 2],
+&nbsp;               [3, 4]]
+<strong>Output</strong>: Rotated Matrix:
+[2, 4]
+[1, 3]</span></pre>
+<p><span style="font-size: 18px;"><strong>Constraints:</strong><br>1 ≤ n ≤ 10<sup>2</sup><br>0 &lt;= mat[i][j] &lt;= 10<sup>3</sup></span></p></div><p><span style=font-size:18px><strong>Company Tags : </strong><br><code>Paytm</code>&nbsp;<code>Microsoft</code>&nbsp;<code>Samsung</code>&nbsp;<code>Adobe</code>&nbsp;<br><p><span style=font-size:18px><strong>Topic Tags : </strong><br><code>Matrix</code>&nbsp;<code>Data Structures</code>&nbsp;