Given a Turing Machine M = ({q0 , q1 }, {0, 1}, {0, 1, B}, δ, B, {q1 }) Where…

2016

Given a Turing Machine

M = ({q0 , q1 }, {0, 1}, {0, 1, B}, δ, B, {q1 })

Where δ is a transition function defined as

δ(q0 , 0) = (q0 , 0, R)

δ(q0 , B) = (q1 , B, R) The language L(M) accepted by Turing machine is given as :

  1. A.

    0* 1*

  2. B.

    00*

  3. C.

    10*

  4. D.

    1*0*

Attempted by 43 students.

Show answer & explanation

Correct answer: B

Answer: The language is all strings consisting only of zeros (including the empty string), i.e. 0*.

Key idea: The machine scans right over zeros and accepts when it reaches the blank symbol. There is no transition for the symbol '1', so any input containing '1' is rejected.

  • Start state q0: on reading '0' the machine stays in q0 and moves right. So any number of consecutive zeros can be read.

  • On reading the blank symbol B while in q0 the machine transitions to q1 and accepts.

  • There is no transition for '1' in q0, so if any '1' appears in the input the machine halts without accepting (the input is rejected).

  • Therefore the set of accepted strings is exactly all strings of the form 0^n for n ≥ 0, i.e. 0*.

Examples: the empty string, "0", "00" are accepted; "1", "01", "10" are rejected.

A video solution is available for this question — log in and enroll to watch it.

Explore the full course: Mppsc Assistant Professor