OpenWritings.net

digraph simple_hierarchy {
	a->b->c;
	b->d;
	a->e->f;
	e->g;
 
	// Drawing edges while preserving the tree layout with constraint=none
	// Very good for annotations.
	edge [color=red,arrowhead=none,constraint=none];
	b->f
	b->g
	d->f
	g->c
}