add SPMD slide

document.tex

@@ -200,6 +200,22 @@ HPCG is representative of lots of scientific codes
 \end{frame}
 
 %---------------------
+
+\begin{frame}
+  \begin{block}{}
+  \Large 
+\textbf{S}ingle\\
+\textbf{P}rogram\\
+\textbf{M}ultiple\\
+\textbf{D}ata\\
+\normalsize
+ \end{block}
+
+\end{frame}
+
+
+%---------------------
+
 \begin{frame}
   \begin{block}{}
   \begin{center}