A common problem that arises in software maintenance is identifying (and then removing) dead code, code that will never be executed no matter what input the program is given. The analogous problem for TMs would be to determine if a state is never entered, no matter what input the TM is given. Prove by reduction that Ldead, the set of pairs (T, s) where T is a Turing machine and s is a dead state, is not recursive

if you go to ask a question say ask, there should be something that looks like this. a camera lens.

the major difference between the two is the objective and the reward of the game. candy crush has a puzzle theme with the objective of meeting a specific quota of points or objects, you are able to gain access to the next level and compete with peers on the process. on duolingo the objective is rather different, you are given sets of questions for you to answer for you to move to the next level and as for the reward, you are able to learn available language as this is an app developed to teach the user about other languages.