问题
L = {<T> | T is a turing machine that recognizes {00, 01}}
Prove L is undecidable.
I am really having difficulties even understanding the reduction to use here.
I'm not asking for free lunch, just a push in the right direction.
回答1:
A direct application of Rice's theorem will let you prove this without doing any work at all.
Some Turing machines recognize {00, 01}. Some don't. The difference is semantic in that it has to do with the strings accepted, not the structure of the automaton. Hence, by Rice's theorem, this set is undecidable.
来源：https://stackoverflow.com/questions/13714971/l-t-t-is-a-turing-machine-that-recognizes-00-01-prove-l-is-undecidable