basicaly i want replace in the last match

Why? If you've just put it there, why would you like to proceed to replace it?

using only regexp and it's funcion like pos

Why? It's odd to tell someone how to solve a problem you can't solve.

I'm just learning, when i tried to replace in the last much i found that as you said I couldn't do this specialy if we have many other information in the middle, but yes puting .* in the front of the expression, it retrieve the last much and other way too is using pos, isn't it?

Likes mathematic, i guess that exists many way to solve a problem and i try to understand all posible way so i could decide in the future, what's use in which case.

Thank ikegami, you guys are really great and I apreciate very much

Nicolais

It's odd to tell someone how to solve a problem you can't solve.

Not necessarily. Perhaps the question could/should have been asked differently, but I look at these questions as an effort by the OP to increase knowledge. Something like "Here I am reading the sections of the Camel that tell about pos and I don't quite get it." So I make up a problem for myself as way to try and understand better. But I can't solve my own problem using the tools that I am trying to learn about.

So the difference is one of perspective. You (ikegami) want to solve the question that was posted in any way possible, and as quickly as possible, so you can get on to the next question. The OP wants to learn something about one piece of the large Puzzle-That-Is-Perl.

So chill. Please. Take a deep breath. Relax your sphincter muscles. Don't try to answer every question posted here. Let some of the other monks have a chance to improve their skills at answering questions.