diff -r 485f38b530ab -r cceed8d66b28 hw04.tex
--- a/hw04.tex	Wed Oct 31 21:46:27 2012 +0000
+++ b/hw04.tex	Thu Nov 01 10:04:30 2012 +0000
@@ -61,7 +61,8 @@
 
 where the three dots stand for arbitrary characters, but not comment delimiters.
 (Hint: You can assume you are already given a regular expression written \texttt{ALL},
-that can recognise any character.)
+that can recognise any character, and a regular expression \texttt{NOT} that recognises
+the complement of a regular expression.)
 
 \item Given the alphabet $\{a,b\}$. Draw the automaton that has two states, say  $q_0$ and $q_1$.
 The starting state is $q_0$ and the final state is $q_1$. The transition