diff -r 1c829680503e -r e6ae724255a8 cws/pre_cw03.tex
--- a/cws/pre_cw03.tex	Tue Nov 24 09:04:06 2020 +0000
+++ b/cws/pre_cw03.tex	Tue Nov 24 23:36:21 2020 +0000
@@ -55,6 +55,16 @@
 \end{lstlisting}%$
 
 
+\subsection*{Hints}
+
+\noindent
+\textbf{For the Preliminary Part:} useful operations for determining
+whether a string is a number are \texttt{.forall} and \texttt{.isDigit}.
+One way to calculate the the power operation is to use \texttt{.pow}
+on \texttt{BigInt}s, like \texttt{BigInt(n).pow(m).toInt}.
+\bigskip
+
+
 \subsection*{Preliminary Part (3 Marks, files postfix.scala, postfix2.scala)}
 
 The \emph{Shunting Yard Algorithm} has been developed by Edsger Dijkstra,