\begin{frame}{Exercise}
  \begin{exampleblock}{}
    Given is the following NFA:
    \begin{center}
      \begin{tikzpicture}[default,node distance=20mm,->]
        \node (q0) [state] {$q_0$}; \draw ($(q0) + (-10mm,0mm)$) -- (q0); 
        \node (q1) [fstate,right of=q0] {$q_1$};
        \node (q2) [state,] at ([xshift=10mm,yshift=-15mm]q0) {$q_2$}; 
        
        \draw (q0) to[bend left=15] node [label,above] {$a$} (q1);
        \draw (q0) to[bend left=-15] node [label,below] {$\lambda$} (q1);
        \draw (q1) to[bend left=0] node [label,below right] {$b$} (q2);
        \draw (q1) to[tloop] node [label,above] {$b$} (q1);
        \draw (q2) to node [label,below left] {$a$} (q0);
      \end{tikzpicture}
    \end{center}
    \emph{Construct a DFA that accepts the same language.}    
  \end{exampleblock}
\end{frame}