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\usepackage{underscore}
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\begin{document}
\pagestyle{empty}
\mbox{}
\newpage
\noindent\marginpar[\hfill Input]{}%
一二三四五六七八九十一二三四五六七八九十
\mbox{一二三四五六七八九十一二三四五六
\texttt{shared_ptr}。}

\vspace{1ex}
\hrule

\noindent\marginpar[\hfill Word]{}%
一二三四五六七八九十一二三四五六七八九十\linebreak
一二三四五六七八九十一二三四五六\linebreak
\texttt{shared_ptr}。

\vspace{1ex}
\hrule

\noindent\marginpar[\hfill \TeX]{}%
一二三四五六七八九十一二三四五六七八九十
一二三四五六七八九十一二三四五六
\texttt{shared_ptr}。
\end{document}