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# 0344. Reverse String

<https://leetcode.com/problems/reverse-string>

## Description

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

**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:**

* `1 <= s.length <= 105`
* `s[i]` is a [printable ascii character](https://en.wikipedia.org/wiki/ASCII#Printable_characters).

**Follow up:** Do not allocate extra space for another array. You must do this by modifying the input array [in-place](https://en.wikipedia.org/wiki/In-place_algorithm) with `O(1)` extra memory.

## ac

```java
```
