Hi, I'm having trouble with reductions and classifying the following language:

L ={ <M> ∀w∈Σ* Tm(|w|) = c }

That is, L is a language of turing machine encodings such that for any input w

the runtime of the machine is a constant c.

The goal is to classify the language - whether its in R, RE\R or outside of RE.

Proof needs to be shown via reduction or usage of the Rice theorem.

If anyone would at least give me a direction to start with it'll be great.

On one hand it would seem it belongs to RE since its blocked by a constant, on the other hand all input is required to be blocked by the running time of c.

Thanks beforehand, GoatHunter.