
diff -r ae039d6ae3f2 -r a1544b804d1e hws/hw01.tex
--- a/hws/hw01.tex	Mon Oct 06 20:55:16 2014 +0100
+++ b/hws/hw01.tex	Fri Oct 10 16:59:22 2014 +0100
@@ -7,58 +7,51 @@
 
 \begin{enumerate}
 
-\item {\bf (Optional)} If you want to run the code presented
-      in the lectures, install the Scala programming language
-      available (for free) from
+\item {\bf (Optional)} If you want to run the code presented in the
+  lectures, install the Scala programming language available (for
+  free) from
 
 \begin{center}
 \url{http://www.scala-lang.org}
 \end{center}
 
-      If you want to follow the code I present during the
-      lectures, read the handout about Scala.
-
-\item {\bf (Optional)} Have a look at the crawler programs.
-      Can you find a usage for them in your daily programming
-      life? Can you improve them? (For example in cases there
-      are links that appear on different recursion levels, the
-      crawlers visit such web-pages several times. Can this be
-      avoided?) 
+      If you want to follow the code I present during the lectures,
+      read the handout about Scala.
 
-\item Read the handout of the first lecture and the handout
-      about notation. Make sure you understand the concepts of
-      strings and languages. 
+\item {\bf (Optional)} Have a look at the crawler programs.  Can you
+  find a usage for them in your daily programming life? Can you
+  improve them? (For example in cases there are links that appear on
+  different recursion levels, the crawlers visit such web-pages
+  several times. Can this be avoided?)
 
-\item In the context of the AFL-course, what is meant by the
-      term \emph{language}?
+\item Read the handout of the first lecture and the handout about
+  notation. Make sure you understand the concepts of strings and
+  languages.  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 regular expression?
+\item Give the definition for regular expressions. What is the meaning
+  of a regular expression? (Hint: The meaning is defined recursively.)
 
-\item Assume the concatenation operation of two strings is
-      written as $s_1 @ s_2$. Define the operation of
-      \emph{concatenating}, written $\_ \,@\, \_$ two sets of
-      strings.
+\item Assume the concatenation operation of two strings is written as
+  $s_1 @ s_2$. Define the operation of \emph{concatenating}, written
+  $\_ \,@\, \_$ two sets of strings.
 
-\item Assume a set $A$ contains 4 strings and a set $B$ 7
-      strings, how many strings are in $A @ B$?
+\item Assume a set $A$ contains 4 strings and a set $B$ 7 strings, how
+  many strings are in $A \,@\, B$?
 
-\item How is the power of a language defined? (Hint: There are
-      two rules, one for $\_^0$ and one for
-      $\_^{n+1}$.)
+\item How is the power of a language defined? (Hint: There are two
+  rules, one for $\_^0$ and one for $\_^{n+1}$.)
 
-\item How many regular expressions are there to match the
-      string $abc$? How many if they cannot include
-      $\epsilon$ and $\varnothing$? How many if they are also
-      not allowed to contain stars? How many if they are also
-      not allowed to contain $\_ + \_$?
+\item How many regular expressions are there to match the string
+  $abc$? How many if they cannot include $\epsilon$ and $\varnothing$?
+  How many if they are also not allowed to contain stars? How many if
+  they are also not allowed to contain $\_ + \_$?
 
-\item When are two regular expressions equivalent? Can you
-      think of instances where two regular expressions match
-      the same strings, but it is not so obvious that they do? For
-      example $a + b$ and $b + a$ do not count\ldots they
-      obviously match the same strings, namely $[a]$ and $[b]$.
-
+\item When are two regular expressions equivalent? Can you think of
+  instances where two regular expressions match the same strings, but
+  it is not so obvious that they do? For example $a + b$ and $b + a$
+  do not count\ldots they obviously match the same strings, namely
+  $[a]$ and $[b]$.
 \end{enumerate}
 
 \end{document}




