**CS-501-CBGSB.Tech., V SemesterExamination, June 2020Choice Based Grading System (CBGS)Theory of Computation**

1. a) Differentiate Mealy machine and Moore machine with diagram.

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b) Design Turing machine to add two number a and b.

2. a) State Pumping Lemma and show that L 1 { a^{i}b^{i }i>=1} is not a regular language.

b) Explain types of Turing machine in detail.

3. a) Prove that CFL are not closed under intersection.

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b) Construct Moore machine for the following Mealy machine.

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4. a) Explain P class problems in detail.

b) What is a trap state in FA? Explain the properties of transition function.

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5. a) Define DFA, List three household applications of finite automata.

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b) What are leftmost and rightmost derivations? Explain with suitable example.

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6. a) What is PDA? Explain instantaneous description of PDA.

b) Show that the following grammar is ambiguous.

S → aSbS|bSaS|∈

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7. a) How can we construct regular grammar from regular expression?

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b) Write given CFG for R.E (011 + 1)*(01)*.

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8. Write short note on any three of the following.

i) Undecidable problem

ii) Two way finite automata

iii) UTM

iv) Multitape

v) Recursively enumerable set