+ \head{Hash functions, \seq: Merkle-Damg\aa{}rd iterated hashing (cont.)}
+
+ \vfil
+ \[ \begin{graph}
+ []!{0; <2cm, 0cm>: <0cm, 0.9cm>::}
+ *+=(1, 0)+[F]{\mathstrut I_0 = I} :[d] *+[F]{F}="f"
+ [urrr] *+=(3, 0)+[F]{\mathstrut x_0} :`d"f" "f" :[d]
+ *+=(1, 0)+[F]{\mathstrut I_1} :[d] *+[F]{F}="f"
+ [urrr] *+=(3, 0)+[F]{\mathstrut x_1} :`d"f" "f" :@{-->}[dd]
+ *+=(1, 0)+[F]{\mathstrut I_{n-1}} :[d] *+[F]{F}="f"
+ [urrr] *+=(3, 0)+[F]{\mathstrut x_{n-1}} :`d"f" "f" :[d]
+ *+=(1, 0)+[F:thicker]{\mathstrut H(x) = I_n}
+ \end{graph} \]
+ \vfil
+\end{slide}
+
+\begin{slide}