I am a newbie/fresher n recently joined codechef.
I currently have very little knowledge.
So can any1 please guide me out.
Just try your hands at the easy problem section especially those problems, which have a lot of successful submissions.
Just like @re_hash said, go to http://www.codechef.com/problems/easy?sort_by=SuccessfulSubmission&sorting_order=desc and try solving them.
the superior ones have already answered you. But in addition you can go through the number of solutions of problems after you solve/try them. this would give you various ways in which it could have been done, or even many-a-times give you knowledge of new codes/functions/tricks.