1. What is the role of parser? Explain the different error recovery strategies. (08 Marks) (Dec.2019/Jan.2020)

2. Construct the LL(1) parsing table for the following productions:

3. E+E + T/T ; T -> T * F/F ; F -> (E)/id (08 Marks) (Dec.2019/Jan.2020)

4. Using operator-precedence parsing algorithm, construct, the table and parse the input string id + id * id. (12 Marks) (Dec.2019/Jan.2020)

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5. Define Handle, viable prefixes. (04 Marks) (Dec.2019/Jan.2020)

6. Define left recursion grammer, eliminate left recursion from the following grammer:

S -> aB|ac|sd|se

B -> bBc|f

C -> g (03 Marks) (June/July 2019)

7. Consider the following context free grammer S -> SS + | SS * | a and the input string aa + a*

i) Give LMD and RMD

ii) Parse tree

iii) Is the grammer ambiguous? Why

iv) Describe the language generated by the grammer

v) Left factor the grammer. (05 Marks) (June/July 2019)

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8. Consider the following grammer with terminals

(, [, ), ]

S ->TS|[S]S|)S|e

T ->(x)

X -> TX|[X] X|e

i) Construct first and follow sets

ii) Construct its LL(1) parsing table

iii) Is this grammer LL(1)?

(08 Marks) (June/July 2019)

9. The following is ambiguous grammer

S ->AS|b

A ->SA|a

Construct for this grammer its collection of sets of LR(O) items. IF we try to build an LR - parsing table for the grammer, there are certain conflicting actions what are they? Suppose we tried to use the parsing table by non-deterministically choosing a possible action whenever there is a conflict, show all the possible sequences of actions on input abab$.

(10 Marks) (June/July 2019)

10. What are the actions of a shift - reduce parser. Design shift - reduce parser for the following grammer on the input 10201 S -> 0 S 0|1 S 1 2. (06 Marks) (June/July 2019)

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11. What is shift reduce parser? Explain the conflicts that may occur during shift reduce parsing (04 Marks) (Dec.2018/Jan.2019)

12. Construct LALR parsing tables for the grammar shown below using LR(1) items.

S -> S

S -> Ce

C -> eC|d(08 Marks) (Dec.2018/Jan.2019)

13. How left recursion can be eliminated from grammars the simple arithmetic expression grammar and rewrite the grammar after removing left recursion. (04 Marks) (Dec.2018/Jan.2019)

14. What is left factoring? Rewrite the following grammer after "left factored"

S -> iEts | iEiSeS|a

E -> b (04 Marks) (Dec.2018/Jan.2019)

15. Write a note on the parser generator yaac (04 Marks) (Dec.2018/Jan.2019)

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16. Construct canonical LR(1) items for, augmented grammer

S' -> S :

S -> Ce

C -> eC|d (08 Marks) (Dec.2018/Jan.2019)

17. What is top down parser? What are key problems in top down parsing? (08 Marks) (June/July 2018)

18. Explain the ambiguity in arithmetic expression. What is the ambiguity in parsing 2 +3 « 42 Explain the solution for it. (08 Marks) (June/July 2018)

19. What is meant by handle processing? How it helps on shift reduce parsing? List the actions of a shift reduce parser. (08 Marks) (June/July 2018)

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20. Form the Action/Goto table for the following grammar:

S ->Aa|bAc|Ba|bBa

A -> d

B -> d

Justify whether the grammar is LR (0) or not. (08 Marks) (June/July 2018)