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\begin{document}
\begin{CJK}{GB}{kai}
\title{��ĵ}
\author{�ҿ�
\maketitle
\tableofcontents
\begin{abstract}
��Ϊ�ѧϰLatex�IJ��ļ
\end{abstract}

\section{��һ�ection}
������ġܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳ

\[y = \left\{ \begin{array}{ll}
 a & \textrm{if $d>c$}\\
 b+x & \textrm{in the morning}\\
 l & \textrm{all day long}
  \end{array} \right.
 \]

�4һΡܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳ

\section{���һ�ection}
������ġܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳ

�4һΡܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳܳ


\end{CJK}
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