Code comments

[Codepoet]

ok...
thanks for mooore information but my question is neverless actual

Where better comment the method ?

1) in *.h
2) in *.cpp
3) 1) and 2)

for your replies i see that first choice is better...then when anybody will be research in my code he must always switch betwwen *.h(for look for comments) and *.cpp(for look for implementation)...

I can't tell you what is better, but that my approach works very good for me: Users of my code never read the implementation. They want to know how to use my methods. That's header only. And editors / IDEs can display the comments as little popup windows while writing code
A maintainer probably already knows how to use the method and jumps directly to the implementation to fix it which should be easier with the comments there which describe what you did.