Definition P-Completeness I've got this problem:


  
  Write down a definition of P-completeness analogous to the definition of
  NP-completeness, i.e., using polynomial-time reductions.
  Which problems are P-complete in this sense, and why?
  Thus, what is the problem, i.e., what must be changed if the goal is to come
  up with a more interesting notion of P-completeness?
  


I have an idea about the first part, but I don't have any idea about the second and third part. The first part is like the NP-Complete, and small change for P-Complete, which is wrong I know, but I want it that way!
You should really work this out yourself, but here are a few hints.

Define P-completeness just as you say, by taking the definition of NP-completeness and changing NP to P. Then ask yourself which problems are P-complete. For a problem to be P-complete it must be in P. What about the other condition? Can you come up with a problem in P which you'd conjecture shouldn't be P-complete under your definition?

Once you've answered part 2, you will be able to answer part 3, so don't despair if you have no idea what they want in part 3 right now.