ALPHA COLLEGE OF ENGINEERING &TECHNOLOGY

DEPARTMENT OF COMPUTER ENGINEERING

ASSIGNMENT: 1

COMPILER DESIGN (170701)

B.E. – 7TH SEM CLASS: CE

LAST DATE OF SUBMISSION: MARKS: 10

1) What are phases of a compiler? Explain the function of each phase with example. Symbol table is necessary for compiler construction; justify your statement with example.

2) a) Design a DFA which accepts set of strings such that every string containing 00 as

a substring but not 000 as substring. b) Construct a FA that will accept those strings of a binary number that are

divisible by three. c) Build an FA that accepts the words baa, ab and add and no other string longer or

shorter. d) Write English descriptions for the languages generated by the following regular

expressions: (a | b)* a(a | b | ε)

3) a. Test whether the following grammar is ambiguous

i. L L ; L | S

ii. S a

b. Eliminate all productions from the following grammars

i)

S aAB | dA

A bAc |

B dB |

ii)

S ABAC

A aA |

B bB |

C C

4) a. Identify and remove unit productions from the following grammars

ii) S A | bb

A B | b

B S | a

iii) S AB

A a

B a | b

C a

D a

E a

b. Remove the useless symbol from the following grammars

i)S aB | bX

A BAd | bSX | a

B aSB | bBX

X SBD | aBx | ad

ii) A xyz | Xyzz

X Xz | xYx

Y yYy | XY

Z Zy | z

NOTE: PROVIDE MODERATE NO OF QUESTIONS

FACULTY NAME: Shraddha Patel