\begin{frame}{Example}
  \begin{exampleblock}{}
    \begin{center}
      \input{tikz/tiles_example.tex}
    \end{center}
  \end{exampleblock}
  \vspace{-1ex}
  \begin{exampleblock}{}
    Consider the input word \alert{$aaa \not\in L(M)$}. Then $n = 2p(3) + 1 = 7$.
    
    \begin{center}\vspace{-1ex}
      \begin{tikzpicture}[default,nodes={rectangle}]
        \mpause[1]{
        \tilew{0}{0}{$\vphantom{W}\Box$}{}{}{}
        \tilew{1}{0}{$\vphantom{W}\Box$}{}{}{}
        \tilew{2}{0}{$\vphantom{W}\Box$}{}{}{}
        \tilew{3}{0}{$q_0,\!a$}{}{}{}
        \tilew{4}{0}{$a$}{}{}{}
        \tilew{5}{0}{$a$}{}{}{}
        \tilew{6}{0}{$\vphantom{W}\Box$}{}{}{}
        }
        \mpause{
        \tilew{0}{1}{$\vphantom{W}\Box$}{}{$\vphantom{W}\Box$}{}
        \tilew{1}{1}{$\vphantom{W}\Box$}{}{$\vphantom{W}\Box$}{}
        \tilew{2}{1}{$\vphantom{W}\Box$}{}{$\vphantom{W}\Box$}{}
        \tilew{3}{1}{$b$}{\rotatebox{90}{$q_0,\!\raisebox{-2pt}{R}$}}{$q_0,\!a$}{}
        \tilew{4}{1}{$q_0,\!a$}{}{$a$}{\rotatebox{90}{$q_0,\!\raisebox{-2pt}{R}$}}
        \tilew{5}{1}{$a$}{}{$a$}{}
        \tilew{6}{1}{$\vphantom{W}\Box$}{}{$\vphantom{W}\Box$}{}
        }
        \mpause{
        \tilew{0}{2}{$\vphantom{W}\Box$}{}{$\vphantom{W}\Box$}{}
        \tilew{1}{2}{$\vphantom{W}\Box$}{}{$\vphantom{W}\Box$}{}
        \tilew{2}{2}{$\vphantom{W}\Box$}{}{$\vphantom{W}\Box$}{}
        \tilew{3}{2}{$b$}{}{$b$}{}
        \tilew{4}{2}{$b$}{\rotatebox{90}{$q_0,\!\raisebox{-2pt}{R}$}}{$q_0,\!a$}{}
        \tilew{5}{2}{$q_0,\!a$}{}{$a$}{\rotatebox{90}{$q_0,\!\raisebox{-2pt}{R}$}}
        \tilew{6}{2}{$\vphantom{W}\Box$}{}{$\vphantom{W}\Box$}{}
        }
        \mpause{
        \tilew{0}{3}{$\vphantom{W}\Box$}{}{$\vphantom{W}\Box$}{}
        \tilew{1}{3}{$\vphantom{W}\Box$}{}{$\vphantom{W}\Box$}{}
        \tilew{2}{3}{$\vphantom{W}\Box$}{}{$\vphantom{W}\Box$}{}
        \tilew{3}{3}{$b$}{}{$b$}{}
        \tilew{4}{3}{$b$}{}{$b$}{}
        \tilew{5}{3}{$b$}{\rotatebox{90}{$q_0,\!\raisebox{-2pt}{R}$}}{$q_0,\!a$}{}
        \tilew{6}{3}{$q_0,\!\Box$}{}{$\Box$}{\rotatebox{90}{$q_0,\!\raisebox{-2pt}{R}$}}
        }
      \end{tikzpicture}\vspace{-2ex}
    \end{center}
    \pause\pause\pause\pause\pause
    The \alert{tiling cannot be completed}.
  \end{exampleblock}
  \bigskip
\end{frame}