Longest Common Prefix

Problem Given an array of strings, find the longest string that is a prefix of every string in the array. If there is no common prefix, return the empty string.

Input / Output

• Input: an array of strings strs.
• Output: the longest common prefix, or "".

Constraints

• 1 <= n <= 200.
• Strings may be empty; an empty string in the array forces an empty result. Comparison is case-sensitive.

Example

• ["flower","flow","flight"] -> "fl"
• ["dog","racecar","car"] -> ""