In this homework assignment, you will create a data structure called a
trie.  A trie, T, is a type of tree which is used to store Strings
from a set S.

A trie has the following properties:

1. Each node of the trie, T, except the root, is labeled with a single letter.

2. The order of the children of any node of T is determined by
alphabetical order.

3. Each node of the trie has a boolean flag, wordEnd, associated with
it which indicates whether or not a String from the set S ends at that
node.

4. The concatentation of the labels from the root node to any node
which is has the wordEnd flag set to true yields a String from S.

5. By definition, all leaves of the trie are have the wordEnd flag set
to true.

6. The height of the trie is equal to the length of the longest string in S.

When a string is inserted into a trie, its first letter is stored as a
child of the root node, its second letter is stored as a child of that
node, its third as a child of that, etc.  The final letter of a string
has the wordEnd flag is set to true.

When inserting words into a trie, you do not want to re-create nodes
that already exist.  For example, if you insert "ARM" into an empty
trie, you will create a child node, of the root labeled "A", a child
node of the "A" node labeled "R", and a child node of the "R" node
labeled "M" whose wordEnd flag is set to true.

Next, if you insert "ART" into the trie containing "ARM", you will
first find that the trie already contains, a node from the root
labeled "A", then you will find that there is a child node of that "A"
node labeled "R", and then you will find that there is no child node
of that "R" node labeled "T", so you will create a new child node of
this "R" node labeled "T", and set its wordEnd flag to be true.

Once you have created the Trie data structure, insert all the words in the 
wordlist.2500 file which I gave you as part of Labs/3.  

Then, read in the file lglass.txt, and for each word you find, print
out two things: if you found the word in the trie, and how many nodes
you needed to traverse to find the word.

You will extend this homework in Homework/8a with binary trees.