Context Free Grammars

I find the entire concept interesting to say the least. There is actually a set of rules for a language that can denote a sandwich. I plan to head to subway with a large index card printed with rules on the front and point to it as I order. But the guy behind the counter could create some kind of infinite sandwich which will end up costing me a pretty penny.

Anyways, I did notice that the example with "a mat beside the dog and a cat saw the mat" was... was close enough to a perfect sentence. BUT, It does get really close to that lolspeak crap that everyone on the internet uses these days.

A simple example: Internets, Intarnets, Interweb, Intarweb, lol internet etc.

S-> CABC
A -> Inter | Intar | Inner
B -> web | net | webs | nets | tube | tubes
C -> lol | ""

Oh man, now I feel retarded. I was about to post a more complex example but my IQ dropped dangerously into the zone reserved for Microsoft Fanboys and /b/tards.

Anyways, another thought. If you had a room full of monkeys and Context free Grammars, eventually they would produce the works of shakespeare.


edit: also waiting for approval to submit A3 related posts I have stored up.
edit2: looking at what I wrote a couple of days later, I realize I may have done something wrong.

Regular Expressions

I am finding this section of the course to be the most satisfying. I find RE's are a material I can grasp a little easier and thus am enjoying writing the problem sets. I even looked over the assignment and it seems to be easier than A2 or A1. Normally when I begin an assignment, I print it out and mark in red my thoughts and ideas before seriously attacking the problems. A3 is a sea of red to my eyes.

Or it could be that I received my A2 mark and it was decent, boosting my morale. Or the fact that I somehow managed to get a perfect score on a problem set for once, a pretty decent achievement for someone with a logic deficiency.

Lately I've been trying to develop applications for the iPhone platform. A regular expression checker came to mind. Then the entire idea of writing software specifically for UofT students came next. Software to aid csc students. I like where this is going. There's no better way to understand the material I'm being taught than through application.

Or maybe I'm dreaming too hard.

Epic Fail.

Well, Assignment 2 and Midterm 2 have come and gone. Overall, I found them both fair.

...Although I should have spotted earlier that one of the functions in question one was the Fibonacci sequence. I remembered as I was doing question 2, but somehow forgot it by the time I got to question three. Note to self: write all epiphanies down immediately.

Knowing that it was a fibonacci could have made it easier to prove. Instead I wrote T(n) down on the leftside and 2F(n+1) -1 on the rightside and tried to unwind them both. I know I'm doing something wrong there. Perhaps I still don't understand the final goal, I need to do more proofs as practice. Me attempting to unwind (always a slow process to me) took the majority of the test and I stupidly didn't leave enough time for the other questions. Perhaps just enough time, I did finish them, but that doesn't mean they're correct. I know I can do it (I managed to do it on Assignment 2). Speed is my major issue. I will work on that for Test 3 and the final.