Lesson 06

Question 1

Parsing

Answer 1

is the process of determining if and how a string of terminals can be generated by a grammar. O (n3)

Question 2

The top-down

Answer 2

is done by starting with the root, labeled with the starting non terminal stmt

Question 3

lookahead symbol.

Answer 3

The current terminal being scanned in the input

Question 4

Predictive Parsing

Answer 4

in which the lookahead symbol unambiguously determines the flow of control through the procedure body for each non terminal

Question 5

The predictive parser consists

Answer 5

of procedures for the non terminals type and simple of the grammar.

Question 6

ɛ Productions

Answer 6

Predictive parser uses an ɛ production as a default when no other production can be used.

Question 7

FIRST()

Answer 7

is the set of terminals that appear as thefirst symbols of one or more strings generated from alpha

Question 8

Left Recursion

Answer 8

When a production for non terminal A starts with a self reference then a predictive parser stuck in loop forever.

Question 9

Left Recursion can

Answer 9

be eliminated by systematically rewriting the grammar using right recursive productions