digraph g {
rankdir=LR

node [shape=plaintext]

subgraph cluster_01 {

	label = "Legend";

	key [label=<<table border="0" cellpadding="2" cellspacing="0" cellborder="0">

	<tr><td align="right" port="i1">Control dependency</td></tr>

	<tr><td align="right" port="i2">Data dependency</td></tr>

	<tr><td align="right" port="i3">Call, param-in, param-out</td></tr>

	<tr><td align="right" port="i4">Summary</td></tr>

	</table>>]

	key2 [label=<<table border="0" cellpadding="2" cellspacing="0" cellborder="0">

	<tr><td port="i1">&nbsp;</td></tr>

	<tr><td port="i2">&nbsp;</td></tr>

	<tr><td port="i3">&nbsp;</td></tr>

	<tr><td port="i4">&nbsp;</td></tr>

	</table>>]

	key:i1:e -> key2:i1:w [style=bold]

	key:i2:e -> key2:i2:w [color=red]

	key:i3:e -> key2:i3:w [style=dashed]

	key:i4:e -> key2:i4:w [color=blue]
}
}