(MEDIUM) Given an ArrayList of words (all uppercase letters) that all have the same length, create and return an output "word" where each letter is the most frequently-occurring letter of the input words, at that index. So with the words:

[SOW, SON, PIG, DOG, ABS]

the output would be "SOG" since S is the most-frequent letter at index 0, O is most-frequent at index 1, and G is most-frequent at index 2. In the case of a tie between two or more letters that occur with the same frequency, use the letter earliest in the alphabet. Preconditions: words has at least one element, all elements of words are uppercase letters of the same length.