cppenv.sty

\usepackage{listings, xcolor}

\lstset{
    columns = fixed,
    basewidth = {0.5em},
    breaklines = true,
    backgroundcolor = \color{white},
    keywordstyle = \color[RGB]{40, 40, 255},
    numberstyle = \footnotesize\color{darkgray},
    commentstyle = \ttfamily\color{violet},
    basicstyle = \small\ttfamily,
    stringstyle = \ttfamily\color[RGB]{128, 0, 0},
    showstringspaces = false,
    language = {[11]C++},
    escapechar = \@
}

\lstnewenvironment{cpp}[1][\small]{\lstset{language = {[11]C++}, basicstyle = #1\ttfamily}}{}

\lstnewenvironment{txt}{\lstset{language = {[plain]TeX}}}{}

\newcommand{\boxilcpp}[1]{\colorbox[rgb]{0.95, 0.95, 0.95}{\lstinline[language = {[11]C++}]$#1$}}

\newcommand{\ilcpp}[1]{\lstinline[language = {[11]C++}, basicstyle = \ttfamily]$#1$}