**Chap. 20:** Know how to construct a pattern matching machine from a regular
expression that I give you. There are only three rules. Once the
machine is constructed, be able to explain how it works (sequence
of states) in matching a pattern (string) that I give you.

**Chap. 22**: Know how to build a Huffman tree, given a sample text to compress.
Know also how to use the tree to compress and decompress messages.

**Chap. 23**: Know how to read a Caesar cipher, given enough hints as to what
it is.

**Chap. 29**: Graphs: Understand the terminology and the concepts behind them
in the Glossary section, pgs. 416-418. Be able to identify phenomena
such as cycles and disconnected components and operations such
as adding or deleting edges from graphs to change their character.
Be able to do this for all the concepts in the Glossary.