Software Engineer ,

Understanding the code and having concept clear are two different things.

Looking at code one will walk through the code to see what's happening. That's fine. Then he will remember that thing that if the problem is this the answer is this

(Remenbers what he has seen)

But there can be many different ways of doing the same thing and one way can be efficient than other.

So its my style. I don't believe in looking at code and understanding thing.

By Concept I mean the algorithm. One must understand the flow (algorithm) then implementing program in any other language would be simple.

So looking at code and following it is easy but creating same thing in better way on our own ot difficult unless we get concept clear.