--- 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}