diff -r 0806e45d873c -r a2c18456c6b7 hws/hw01.tex
--- a/hws/hw01.tex	Fri Sep 25 08:51:12 2015 +0100
+++ b/hws/hw01.tex	Fri Sep 25 17:39:02 2015 +0100
@@ -5,6 +5,8 @@
 
 \section*{Homework 1}
 
+\HEADER
+
 \begin{enumerate}
 
 \item {\bf (Optional)} If you want to run the code presented in the
@@ -44,7 +46,7 @@
 
 \item Let $A = \{[a], [b], [c], [d]\}$. How many strings are in $A^4$?
   Consider the case of $A^4$ where one of the strings in $A$ is the 
-  empty string.
+  empty string, for example $A = \{[a], [b], [c], []\}$.
 
 \item How many regular expressions are there to match the string
   $abc$? How many if they cannot include $\epsilon$ and $\varnothing$?