Is the following language decidable?
L = {(M) : M performs at least 100 steps on every accepted input.}
I tried to use reduction from the halting problem, but still no dice.
Asked
Active
Viewed 514 times
0
-
1Cross-posted: http://cs.stackexchange.com/q/70747/755, http://stackoverflow.com/q/42428695/781723. Please do not post the same question on multiple sites. Each community should have an honest shot at answering without anybody's time being wasted. – D.W. Feb 24 '17 at 19:23
1 Answers
2
Yes, it is decidable. There is a limited amount of input that any Turing machine could look at in ≤ 100 steps, so you can test a simulation of any given machine $M$ against all of those possibilities.
Matt Timmermans
- 494
- 3
- 8
-
2Next time, consider waiting until the OP reveals what effort, if any, they expended on solving the problem themselves. – Yuval Filmus Feb 24 '17 at 03:17