If a Turing machine program consists of the following four instructions:
(1,0,1,2,R)
(1,1,0,2,R)
(2,0,0,2,R)
(2,b,b,2,L)
Then which of the following is a halting configuration?
A) ... b 1 1 b b b ... (current state = 2, symbol 1 is being read)
B) ... b 1 1 b b b ... (current state = 1, symbol 1 is being read)
C) ... b 1 0 b b b ... (current state = 1, symbol 0 is being read)
D) ... b 1 0 b b b ... (current state = 2, symbol 0 is being read)

Question

Quizplus · Accepted Answer

The Turing machine halts when it reaches a configuration where no instruction applies. In configuration A, the current state is 2 and the symbol being read is 1, for which there is no instruction, thus it is a halting configuration.

If a Turing Machine Program Consists of the Following Four