Fix exercise 2 path mistake in T08

Tutorials/T08-CppExamples/slides/T8.tex

@@ -269,7 +269,7 @@ We will discuss what this does on the next slides.
 \begin{frame}[t]
 \frametitle{Exercise 2:  Run the Preprocessor Without Guards}
 \begin{block}{Exercise 2}
-The code in \texttt{examples/compilation/withguards} contains the same code as the last example with the header guards removed.\\[\baselineskip]
+The code in \texttt{examples/compilation/noguards} contains the same code as the last example with the header guards removed.\\[\baselineskip]
 
 Look at main.cpp.  Notice that main.cpp includes B.h, and {\bf B.h includes A.h}.  Notice that {\bf main.cpp also includes A.h}.\\[\baselineskip]