Tribhuvan University
Bachelor of Science in Computer Science and Information Technology
Semester 4 · TU Board 2079
Course Title: Theory of Computation (CSC262)
Full Marks: 60Pass Marks: 24Time: 3 hours
Candidates are required to give their answers in their own words as far as practicable. The figures in the margin indicate full marks.
Group A
Attempt any TWO questions(2 × 10 = 20)
- 1.10
Show that, For any NFA N=(Q, ∑, δ, q0, F) accepting language L=∑, There is a DFA D= (Q', ∑', q0′, δ', F') accepting the same language L.
- 2.10
State and prove the Pumping Lemma for regular languages. How can you show with example that pumping lemma is used to prove that a given language is not a regular? Explain.
- 3.10
Given the following expression grammar for simple arithematic expression with operator + and *.
E→ E+T | T
T → T+F | F
F → (E) | a
Remove the left recursion from this grammar then simplify and convert to CNF.
Group B
Attempt any EIGHT questions(8 × 5 = 40)
- 4.5
Explain the ε-closure of states on an ε-NFA with suitable examples.
- 5.5
Convert the following regular expression into equivalent Finite Automata
a) (0+1)*10(1+0)
b) 1*0(0+1)*1
- 6.5
Define the term: Parse Tree, left-most and right-most derivation, sentential form and ambiguity with example.
- 7.5
Give the formal definiton of Push Down Automata. How CFG can be converted into equivalent PDA. Explain with an example.
- 8.5
Define regular grammar. Also explain the method of converting right linear grammar into equivalent finite automata.
- 9.5
Construct a Turing machine that accepts the language, L = { a^n b^n | n≥0}
- 10.5
Define Turing machine and its roles.
Answer comingAlso asked in 2078
- 11.5
Explain about the complexity classes p, NP and NP-Complete.
- 12.5
Write short notes ( Any two ) :
a) Big Oh, Big Omega and Big Theta
b) Tractable and Intractable Problems
c) Chomsky Hierarchy
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