Got AC 0.001 sec from the first effort :) I saw many requests for clarification here, but it's easier to describe grammar in terms of behavior.

Go sequentially through input data.

1. If you meet '{' - everything until closest corresponding '}' is a single comment, no matter what's inside. '}' corresponds to '{' if all {,} characters between them form valid bracket sequence.

2. If you meet '//' - everything until '\n' is a single comment, no matter what's inside.

3. If you meet ' - everything until next ' is a string, no matter what's inside.

3. If you meet '#' followed by a digit - everything until first non-digit is a string.

4. If you meet a digit, then everything until first non-digit is a number. If first non-digit character is '.' AND it is followed by another digit, then this post-dot digit sequence is appended to the number as well as the dot itself. I.e. "1.23" is a single number, but "123.a" is number '123' followed by '.', followed by identifier 'a'.

5. If you meet underscore or letter, everything until first non-digit-non-underscore-non-letter is an identifier. It may be a keyword.

6. Output all other characters as is.

Edited by author 17.08.2008 01:02

These statements should be stated in problem
description. They are all right and to recreate them
I tried 50 submissions.
In western sytes it is a rule punctual and clear
descriptions all conditions but in our country
often used believeness in super talantedness of us.

Edited by author 10.01.2009 20:26

Really helpful! Link to this post should be added to the statement :-)