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 \title{CSP Exercise 01 Solution}

 \author{Eugen Sawin}

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 \begin{document}

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 \section*{Exercise 1.1a}

 \begin{tabular}{|c|c|c||c|c|c||c|c|c|}

   \hline

   5&3&6 &4&7&2 &8&1&9 \\ \hline

   4&2&1 &6&9&8 &5&7&3 \\ \hline

   7&8&9 &1&5&3 &4&6&2 \\ \hline\hline

   8&6&3 &9&2&4 &1&5&7 \\ \hline

   1&7&5 &8&3&6 &9&2&4 \\ \hline

   2&9&4 &5&1&7 &6&3&8 \\ \hline\hline

   3&1&8 &2&4&5 &7&9&6 \\ \hline

   9&4&7 &3&6&1 &2&8&5 \\ \hline

   6&5&2 &7&8&9 &3&4&1 \\ \hline

 \end{tabular}

 \end{document}