321 - Quiz07

One of the following valid Regular Expression is equivalent to the Regular Expression a? Which one is it?

• a|ε

• [a]

• a+ε

• not a valid RE

RE: (a|b)* is equivalent to b*a*

• No

• Yes

• maybe

• I should guess

RE: (a|b)* is equivalent to (a*b*)*

• No

• yes

• Maybe

• I should guess

The Cambridge notation for z = x + 2 * y is?

• (z (x (2 y*)+)=)

• (= z (+ x (* 2 y)))

• = z + x * 2 y

• 

Before you can use a grammar to create a LL(1) parser, you must

• Remove Left Recursion

• Calculate the First set for each Terminal

• Make sure each production rule has a single RHS

• make sure the current sentential form look like αAβ

LR parsers are table driven; uses a Left-to-right reading of input; create Rightmost derivation (in reverser order)

• True

• False

Regular Expression: [ch]?at - matches which of the following?

• hat

• cat

• at

• chat

• hcat

If we have the following production rules?

• S

• R

• T

• P

• First(R)= { c d f }

• First(R)= { c d f b }

• First(R)={ a b c d f }

• First(R)= { c d f b ε }

Consider S->0S1 | ε T={0 1} N={S} which of the following are true?

• It is not a Regular Grammar

• 0ⁿ 1ⁿ | n>=0 (same number of 1's as 0's for n>= 0)

• An equivalent RE: 0⁺1⁺

• the empty string is a member of this language

• The empty string is NOT a member of the language