--- a/slides/slides03.tex	Wed Oct 14 17:31:57 2020 +0100
+++ b/slides/slides03.tex	Thu Oct 15 09:22:33 2020 +0100
@@ -5,9 +5,15 @@
 \usepackage{../langs}
 \usepackage{../data}
 
+\usepackage{tcolorbox}
+\newtcolorbox{mybox}{colback=red!5!white,colframe=red!75!black}
+\newtcolorbox{mybox2}[1]{colback=red!5!white,colframe=red!75!black,fonttitle=\bfseries,title=#1}
+\newtcolorbox{mybox3}[1]{colback=Cyan!5!white,colframe=Cyan!75!black,fonttitle=\bfseries,title=#1}
+
+
 \hfuzz=220pt 
 
-\pgfplotsset{compat=1.11}
+\pgfplotsset{compat=1.17}
 
 \newcommand{\bl}[1]{\textcolor{blue}{#1}}  
 
@@ -1571,12 +1577,6 @@
 \end{frame}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
 
-
-
-
-
-
-
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \begin{frame}[c]
 \frametitle{Negation}
@@ -1607,6 +1607,26 @@
 \end{frame}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
+
+\begin{frame}[c]
+\frametitle{Housekeeping}  
+\begin{mybox3}{}
+  The deadline for CW2 is 6 November (thanks to Arshdeep Pareek
+  for pointing this out).
+\end{mybox3}
+\end{frame}
+
+\begin{frame}[c]
+\begin{mybox3}{}
+  I always thought dfa's needed a transition for each state for each
+  character, and if not it would be an nfa not a dfa. Is there an
+  example that disproves this?
+\end{mybox3}
+\end{frame}
+
+\begin{frame}<1-12>[c]
+\end{frame}
+
 \end{document}
 
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