14\. Longest Common Prefix

Easy

Write a function to find the longest common prefix string amongst an array of strings.

If there is no common prefix, return an empty string `""`.

**Example 1:**

**Input:** strs = ["flower","flow","flight"]

**Output:** "fl" 

**Example 2:**

**Input:** strs = ["dog","racecar","car"]

**Output:** ""

**Explanation:** There is no common prefix among the input strings. 

**Constraints:**

*   `1 <= strs.length <= 200`
*   `0 <= strs[i].length <= 200`
*   `strs[i]` consists of only lower-case English letters.