
diff -r bea2dd1c7e73 -r ffde837b1db1 hws/hw01.tex
--- a/hws/hw01.tex	Thu Sep 26 10:52:54 2013 +0100
+++ b/hws/hw01.tex	Thu Sep 26 11:05:54 2013 +0100
@@ -18,6 +18,9 @@
 \item {\bf (Optional)} Have a look at the crawler programs. 
 Can you find a usage for them in your daily programming life?
 
+\item Read the handout of the first lecture and make sure you
+understand the concepts of strings and languages. 
+
 \item In the context of the AFL-course, what is meant by the term \emph{language}?
 
 \item Give the definition for regular expressions. What is the meaning of a 
@@ -29,8 +32,6 @@
 \item How is the power of a language defined? (Hint: There are two rules, one for $\_\!\_^0$ and
 one for $\_\!\_^{n+1}$.)
 
-\item Given the regular expressions $r_1 = \epsilon$ and $r_2 = \varnothing$ and $r_3 = a$.
-How many strings can the regular expressions $r_1^*$, $r_2^*$ and $r_3^*$ each match?
 
 \end{enumerate}
 




