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+%
+% effizient.tex -- Effiziente Berechnung der Potenz
+%
+% (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule
+%
+\bgroup
+\definecolor{darkgreen}{rgb}{0,0.6,0}
+\begin{frame}[t]
+\setlength{\abovedisplayskip}{5pt}
+\setlength{\belowdisplayskip}{5pt}
+\frametitle{Effiziente Berechnung}
+\vspace{-20pt}
+\begin{columns}[t,onlytextwidth]
+\begin{column}{0.48\textwidth}
+\begin{block}{Prinzip}
+\begin{enumerate}
+\item<3-> {\color{red}Bits mit Shift isolieren}
+\item<4-> {\color{blue}Laufend reduzieren}
+\item<5-> {\color{darkgreen}effizient quadrieren}
+\end{enumerate}
+\end{block}
+\end{column}
+\begin{column}{0.48\textwidth}
+\begin{block}{Algorithmus}
+\begin{center}
+\begin{tikzpicture}[>=latex,thick]
+\uncover<3->{
+\fill[color=red!20] (2.3,-2.44) rectangle (3.8,-1.98);
+\fill[color=red!20] (1.45,-3.88) rectangle (3.2,-3.42);
+}
+\uncover<4->{
+\fill[color=blue!20] (2.15,-2.94) rectangle (3.7,-2.48);
+}
+\uncover<5->{
+\fill[color=darkgreen!20] (1.45,-4.37) rectangle (3.8,-3.91);
+}
+\node at (0,0) [below right] {\begin{minipage}{6cm}\obeylines
+{\tt int potenz(int $a$, int $n$) \{}\\
+\hspace*{0.7cm}{\tt int m = 1;}\\
+\hspace*{0.7cm}{\tt int q = $a$;}\\
+\uncover<2->{%
+\hspace*{0.7cm}{\tt while ($n$ > 0) \{}\\
+\uncover<3->{%
+\hspace*{1.4cm}{\tt if (0x1 \& $n$) \{}\\
+\uncover<4->{%
+\hspace*{2.1cm}{\tt m *= q;}\\
+}%
+\hspace*{1.4cm}{\tt \}}\\
+\hspace*{1.4cm}{\tt $n$ >{}>= 1;}\\
+}%
+\uncover<5->{%
+\hspace*{1.4cm}{\tt q = sqr(q);}\\
+}%
+\hspace*{0.7cm}{\tt \}}\\
+}%
+\hspace*{0.7cm}{\tt return m;}\\
+{\tt \}}
+\end{minipage}};
+\end{tikzpicture}
+\end{center}
+\end{block}
+\end{column}
+\end{columns}
+\end{frame}
+\egroup