Update branching practical with three-way merge

branching/branching_handouts.tex

@@ -17,15 +17,20 @@ Working with branches in Git practical.
 We'll work from the repository you created in the previous practical.
 
 \begin{itemize}
-  \item \emph{Question:} What is you current branch and what is the hash of
+  \item \emph{Question:} What is your current branch and what is the hash of
     the commit it points to?
   \item \emph{Question:} What does the commit graph of you repository look
-    like?
+    like? Can you draw it on paper?
 \end{itemize}
 \emph{Hint:} Use \texttt{git log} with the appropriate arguments.
 
 \bigskip
 
+As an alternative to \texttt{git log}, you can also try a graphical viewer
+such as \texttt{gitg} (installed on the course laptops) or \texttt{gitk}.
+
+\bigskip
+
 \subsubsection*{Implement a feature in a new branch.}
 Let's do some real work (e.g., add some documentation to the project).
 
@@ -73,4 +78,26 @@ Merge your feature branch into \texttt{master}.
 
 Since you merged it, you can now delete the feature branch.
 
+\bigskip
+
+\subsubsection*{A three-way merge.}
+Unless you were extremely zealous, the last section produced a fast-forward
+merge.
+
+\bigskip
+
+\begin{itemize}
+  \item \emph{Question:} Can you think of a way to get a three-way merge?
+\end{itemize}
+
+\bigskip
+
+Manipulate your repository in such a way that the commit graph contains a
+merge commit (created by a three-way merge).
+
+\begin{itemize}
+  \item \emph{Question:} What does the commit graph of you repository look
+    like now?
+\end{itemize}
+
 \end{document}