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\newcounter{task}
\newcommand{\task}{\stepcounter{task}\paragraph{Task \thetask~--~Solution.}\ \\}

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% Theorems
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\newtheorem{thm}{Theorem}[section]
\newtheorem{cor}[thm]{Corollary}
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\begin{document}
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% Title
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\title{Introduction to Modern Cryptography\\
  \smallskip
  \Large{Solution to Problem Set 1}
}
\author{Max Mustermann and Maxi Mustermann\\
  \normalsize Matr.no: 123456, 123654\\
  \smallskip
  \normalsize Bauhaus-Universit\"at Weimar\\
}
\date{\today}
\maketitle

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% EDIT FROM HERE
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\task
Solutions to Task 1

\begin{align*}
  c^2 &= a^2 + b^2 \\
  c   &= m^{e} \bmod n
\end{align*}

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\task
Solutions to Task 2


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\end{document}
