Find Common Characters(LeetCode 1002):

Problem

Given a string array words, return an array of all characters that show up in all strings within the words (including duplicates). You may return the answer in any order.

 

Example 1:

Input: words = ["bella","label","roller"]
Output: ["e","l","l"]

Example 2:

Input: words = ["cool","lock","cook"]
Output: ["c","o"]

 

Constraints:

  • 1 <= words.length <= 100
  • 1 <= words[i].length <= 100
  • words[i] consists of lowercase English letters.