
diff -r f345e89895f5 -r fba480bbc9f7 hws/hw01.tex
--- a/hws/hw01.tex	Mon Jun 29 21:05:34 2020 +0100
+++ b/hws/hw01.tex	Mon Jun 29 21:13:49 2020 +0100
@@ -79,7 +79,19 @@
       $[b]$.
 
 \item What is meant by the notions \emph{evil regular expressions}
-      and by \emph{catastrophic backtracking}? 
+  and by \emph{catastrophic backtracking}?
+
+\item Given the regular expression $(a + b)^* \cdot b \cdot (a + b)^*$,
+  which of the following regular expressions are equyivalent
+
+\begin{center}
+\begin{tabular}{ll}    
+  1) & $(ab + bb)^* \cdot (a + b)^*$\\                     % no
+  2) & $(a + b)^* \cdot (ba + bb + b) \cdot (a + b)^*$\\   % yes
+  3) & $(a + b)^* \cdot (a + b) \cdot (a + b)^*$           % no
+\end{tabular}
+\end{center}
+  
 
 \item \POSTSCRIPT  
 \end{enumerate}




