<h2><a href="https://leetcode.com/problems/reverse-vowels-of-a-string/">345. Reverse Vowels of a String</a></h2><h3>Easy</h3><hr><div><p>Given a string <code>s</code>, reverse only all the vowels in the string and return it.</p>

<p>The vowels are <code>'a'</code>, <code>'e'</code>, <code>'i'</code>, <code>'o'</code>, and <code>'u'</code>, and they can appear in both lower and upper cases, more than once.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre><strong>Input:</strong> s = "hello"
<strong>Output:</strong> "holle"
</pre><p><strong class="example">Example 2:</strong></p>
<pre><strong>Input:</strong> s = "leetcode"
<strong>Output:</strong> "leotcede"
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= s.length &lt;= 3 * 10<sup>5</sup></code></li>
	<li><code>s</code> consist of <strong>printable ASCII</strong> characters.</li>
</ul>
</div>