--- a/hws/hw09.tex	Fri Oct 12 10:16:54 2018 +0100
+++ b/hws/hw09.tex	Sat Oct 13 13:51:28 2018 +0100
@@ -41,6 +41,11 @@
 ifeq label
 \end{lstlisting}
 
+
+\item Early in the module, we saw that the regular expression matchers
+  in Java, Python and Ruby are very slow with some (basic) regular
+  expressions. What is the main reason for this ineffcient computation?
+
 \item \POSTSCRIPT  
 
 %  \item It is true (I confirmed it) that