344\. Reverse String

Easy

Write a function that reverses a string. The input string is given as an array of characters `s`.

You must do this by modifying the input array [in-place](https://en.wikipedia.org/wiki/In-place_algorithm) with `O(1)` extra memory.

**Example 1:**

**Input:** s = ["h","e","l","l","o"]

**Output:** ["o","l","l","e","h"]

**Example 2:**

**Input:** s = ["H","a","n","n","a","h"]

**Output:** ["h","a","n","n","a","H"]

**Constraints:**

*   <code>1 <= s.length <= 10<sup>5</sup></code>
*   `s[i]` is a [printable ascii character](https://en.wikipedia.org/wiki/ASCII#Printable_characters).