Week Ten

Monday,
---------- Nov. 10, 2008
We discussed different operations on regular expressions and how to use these rules to, I do not know if I can put it this way, "simplify" regular expression. Then Professor Danny mentioned that finding the intersection of two languages (or regular expressions) can be really tricky, but to solve this issue we use FSAs.
DFSA, Deterministic Finite State Automata, is a machine designed to represent a regular expressions. When given a string input, it determines whether this string is denoted by the regular expression or not.


Wednesday,
---------- Nov. 12, 2008
We talked more about DFSAs today and how to represent them in terms of their states and transitions. There is not much to write about; DFSAs looked to me like a code with if statements instead of states. The example we did in today's lecture was a really simple DFSA but I know things will get much complicated pretty soon.


Friday,
-------- Nov. 14, 2005
We learned how to design a DFSA today by establishing a state invariant which lists all states and explains each one of them.