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\usepackage{multicol}



\begin{document}

\title{Episode 19 -- Eulerian graphs}
\subtitle{European section -- Season 2}
\date{}

\begin{frame}
  \titlepage
\end{frame}

\begin{frame}{A pencil problem (1)}

\begin{center}
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\psline[linecolor=qrqrqr](7,-1)(7,5)
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\end{center}


\end{frame}


\begin{frame}{A pencil problem (2)}

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\end{center}


\end{frame}

\begin{frame}{Walking through a house (1)}

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\end{center}

 

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\begin{frame}{Walking through a house (2)}

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\psline(3,1)(3,2)
\psline(3,2)(1,2)
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\psline(2,2)(2,3)
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\psline(6,1)(6,2)
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\psline(-1,-1)(4,-1)
\psline(5,-1)(10,-1)
\end{pspicture*}
\end{center}

 

\end{frame}


\begin{frame}{The bridges of Königsberg}

\begin{center}
\begin{tabular}{cc}
\includegraphics[width=4cm]{s02e19/euler.eps}
& \includegraphics[width=4cm]{s02e19/castle.eps}\\ \pause
Leonhard Euler (1707 -- 1783)
& Königsberg Castle before WWI \\
\end{tabular}
\end{center}


\end{frame}

\begin{frame}{The bridges of Königsberg}

\begin{center}
\includegraphics[width=9cm]{s02e19/konigsberg.eps}
\end{center}

\end{frame}

\begin{frame}{The bridges of Königsberg}

\begin{center}
\includegraphics[width=7cm]{s02e19/kaliningrad.eps}
\end{center}

\end{frame}





\end{document}
