Trie

The trie is another interesting data structure—in particular, the way in which it is pronounced! Depending on your mother tongue, intuition might dictate a way, but—according to Wikipedia—the name was selected thanks to Edward Fredkin, who pronounced this type of tree differently, namely like trie in retrieval. Many English speakers resort to saying something along the lines of "try" though.

With that out of the way, what does the trie actually do for it to deserve a different name? It transpires that using retrieval was not a bad idea: tries store strings.

Imagine having to store the entire vocabulary of this book in a way to find out whether certain words are contained within the book. How can this be done efficiently?

After the previous sections, you should already have an answer, but if you think about strings—they are stored as arrays or lists of char instances—it would use a good amount of memory. Since each word has to use letters from the English alphabet, can't we use that?

Tries...