CSC262 Theory of Computation

Theory of Computation TU Board 2078 question paper

12 questionsSit this paper (timed)

Tribhuvan University

Bachelor of Science in Computer Science and Information Technology

Semester 4 · TU Board 2078

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.

Attempt any two Questions (2 x 10 = 20)(2 × 10 = 20)

  1. 1.

    Give the formal definition of DFA and NFA. How NFA can be converted into eqivalent DFA? Explain with suitable example.

    10
  2. 2.

    Find the minimum state DFA for the given DFA below:

    States
    Input
    0
    1
    A
    B
    F
    B
    E
    C
    C
    B
    D
    *D
    E
    F
    E
    B
    C
    F
    B
    A

    10
  3. 3.

    Construct a Turing Machine that accepts the language of odd length strings over alphabet {a, b}. Give the complete encoding for this TM as well as its input string w = abb in binary alphabet that is recognized by Universal Turing Machine.

    10
  4. 4.

    Define the term alphabet, prefix and suffix of string, concatenation and Kleen closure with example.

    10
  5. 5.

    Give the regular expressions for the following language over alphabet {a, b}.

    1. Set of all strings with substring bab or abb.
    2. Set of all strings whose 3^rd symbol is 'a' and 5^th symbol is 'b'.
    10
  6. 6.

    Show that L = { a^n | n is a prime number } is not a regular language.

    10
  7. 7.

    Explain about the Chomsky's Hierarchy about the language and programs.

    10
  8. 8.

    Define a Push Down Automata. Construct a PDA that accepts L = {a^nb^n | n > 0}

    10
  9. 9.

    Construct the following grammer into Chomsky Normal Form.

    S → abSb | a | aAb

    A → bS | aAAb | ε

    10
  10. 10.

    Define Turing Machine and explain its different variations.

    10
  11. 11.

    Whar do you mean by computational Complexity? Explian about the time and space complexity of a Turing machine.

    10
  12. 12.

    Explain the term Intractability. Is SAT problem is intractable? Justify

    10

Attempt any Eight Questions(8 × 5 = 40)

  1. 1.

    Give the formal definition of DFA and NFA. How NFA can be converted into eqivalent DFA? Explain with suitable example.

    10
  2. 2.

    Find the minimum state DFA for the given DFA below:

    States
    Input
    0
    1
    A
    B
    F
    B
    E
    C
    C
    B
    D
    *D
    E
    F
    E
    B
    C
    F
    B
    A

    10
  3. 3.

    Construct a Turing Machine that accepts the language of odd length strings over alphabet {a, b}. Give the complete encoding for this TM as well as its input string w = abb in binary alphabet that is recognized by Universal Turing Machine.

    10
  4. 4.

    Define the term alphabet, prefix and suffix of string, concatenation and Kleen closure with example.

    10
  5. 5.

    Give the regular expressions for the following language over alphabet {a, b}.

    1. Set of all strings with substring bab or abb.
    2. Set of all strings whose 3^rd symbol is 'a' and 5^th symbol is 'b'.
    10
  6. 6.

    Show that L = { a^n | n is a prime number } is not a regular language.

    10
  7. 7.

    Explain about the Chomsky's Hierarchy about the language and programs.

    10
  8. 8.

    Define a Push Down Automata. Construct a PDA that accepts L = {a^nb^n | n > 0}

    10
  9. 9.

    Construct the following grammer into Chomsky Normal Form.

    S → abSb | a | aAb

    A → bS | aAAb | ε

    10
  10. 10.

    Define Turing Machine and explain its different variations.

    10
  11. 11.

    Whar do you mean by computational Complexity? Explian about the time and space complexity of a Turing machine.

    10
  12. 12.

    Explain the term Intractability. Is SAT problem is intractable? Justify

    10

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