# =-=-=-= DAY 11 [Medium] =-=-=-=
#
# Implement an autocomplete system. That is, given a query string s and a set of
# all possible query strings, return all strings in the set that have s as a
# prefix.
# 
# For example, given the query string de and the set of strings [dog, deer, deal],
# return [deer, deal].
# 
# Hint: Try preprocessing the dictionary into a more efficient data structure to
# speed up queries.
