How can I apply different styles to different classes of identifiers?

I am creating a custom style for the lstlisting package, with some custom colors for certain words. I am trying to define different "classes" of words, where each class has a certain property, like color, etc. Like this:

name: class1
Keywords: for, int, cout
style: red, underlined

name: class2
keywords: double, std
style: blue, bold

From what I was able to understand from other discussions, the \lstset command has to be used, with the emphkeyword. I have two problems:

1. How do I define multiple classes, where each has different keywords and properties?
2. How do I highlight things like #include or <iostream>, without clashing with other parts of the code (for example in loops where there is usually a <) ?

What I have so far is the following:

\documentclass[a4paper]{article}\usepackage{listings}\usepackage{color}%Custom Colors\definecolor{plainText}{RGB}{74,131,31}\definecolor{comments}{RGB}{74,131,31}\definecolor{strings}{RGB}{180,54,34}\definecolor{numbers}{RGB}{44,45,211}\definecolor{keywords}{RGB}{160,49,158}\definecolor{preprocessorStatements}{RGB}{109,75,48}\definecolor{classNames}{RGB}{101,63,165}\lstset{frame=tb,  language=C++,  aboveskip=3mm,  belowskip=3mm,  showstringspaces=false,  columns=flexible,  basicstyle={\small\ttfamily},  numbers=left,  numberstyle=\tiny\color{plainText},  keywordstyle=\color{keywords},  commentstyle=\color{comments},  stringstyle=\color{strings},  breaklines=true,  breakatwhitespace=true  tabsize=4}\begin{document}\lstinputlisting[tabsize=4]{main.cpp}\end{document}

As an example you can use this

#include <iostream>using namespace std;int main() {    double var1 = 3.2;    int var2 = 3;    for (int i=0; i<var2; i++) {        cout << i << endl;    }    return 0;} 

Thanks in advance