For entertainment you should check out live podcasts are my favDoug Loves Movies Movie trivia contest with hilarious guestsPete Holme ' s You Made it Weird . again only live episodesMatt Kirshen et al in Probably Science . comedy , discussions , science Smodcast kevin Smith and Scot Mosier . Fantastic improv in most episodesThe Bugle Satire kings John Oliver and Andy Zaltzman <| sep |> There ' s quite a bit in this post that seems questionable . A lot are fairly nitpicky like conflating big O notation with asymptotic analysis or making it sound like Unicode is an alphabet , but your solution is questionable . There are big implications in switching from a dictionary to a sorted dictionary how do you handle insertions and deletions from a sorted dictionary in O 1 time ? and you ' ve not mentioned them at all that seems like a massive mistake to make in an interview . It also seems weird that you mention the importance of knowing big O notation and then proceed not to use it anywhere . Also if you get a problem like this in an interview they ' re probably going to expect you to know what a trie is and why it ' s relevant here , even if they don ' t expect you to implement that solution . Your suggestion to hash all prefixes is basically a naive prefix tree that uses way too much memory . Overall I think there are much better sources that cover the same information in more depth . A decent example is this video covering the technical interview at Google , which is applicable to a wide variety of tech companies . oWbUtlUhwa 8