Question 1

Consider the following grammar:
S ? FR
R ? S | ?
F ? id
In the predictive parser table, M, of the grammar the entries M[S, id] and M[R, $]respectively.

Accepted Answer

A) {S ? FR} and {R ? ? } 
B) {S ? FR} and { } 
C) {S ? FR} and {R ? *S} 
D) {F ? id} and {R ? ?}

Question 2

Consider the following expression grammar. The seman-tic rules for expressioncalculation are stated next to each grammar production.
E ? number E.val = number. val
| E '+' E E(1).val = E(2).val + E(3).val
| E '×' E E(1).val = E(2).val × E(3).val
The above grammar and the semantic rules are fed to a yacc tool (which is an LALR (1)parser generator) for parsing and evaluating arithmetic expressions. Which one of thefollowing is true about the action of yacc for the given grammar?

Accepted Answer

A) It detects recursion and eliminates recursion 
B) It detects reduce-reduce conflict, and resolves 
C) It detects shift-reduce conflict, and resolves the conflict in favor of a shift over a reduce action 
D) It detects shift-reduce conflict, and resolves the conflict in favor of a reduce over a shift action

Question 3

Debugger is a program that

Accepted Answer

A) allows to examine and modify the contents of registers 
B) does not allow execution of a segment of program 
C) allows to set breakpoints, execute a segment of program and display contents of register 
D) All of the above

Question 4

A canonical set of items is given below
S --> L. > R
Q --> R.
On input symbol < the set has

Accepted Answer

A) a shift-reduce conflict and a reduce-reduce conflict. 
B) a shift-reduce conflict but not a reduce-reduce conflict. 
C) a reduce-reduce conflict but not a shift-reduce conflict. 
D) neither a shift-reduce nor a reduce-reduce conflict.

Exam 3: Compiler Construction and Parsing Algorithms

Consider the following grammar: S ? FR R ? S | ? F ? id In the predictive parser table, M, of the grammar the entries M[S, id] and M[R, $]respectively.

Debugger is a program that

A canonical set of items is given below S --> L. > R Q --> R. On input symbol < the set has