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\begin{document}

    \title{Домашняя работа по дискретной математике}
    \author{Романов Владимир\\
    ФКН ПМИ 191-1}
    \maketitle
    \begin{exercise}{1}
        \begin{proof}
            $ $\\
        \end{proof}
    \end{exercise}
\end{document}