digraph pdf {
    entry [label="enter f()", style = filled];
	entry -> while [style = bold];
	entry -> D [color = grey];
	while [label="while (X)", style = filled];
    C [style="bold,filled"]
    "if (Y)" [style = filled];
    "if (Z)"
	while -> {"if (Y)"} -> while [style = bold];
    break2 [style = filled];
    break1
	"if (Y)" -> {"if (Z)"} [color = grey];
	"if (Y)" -> C [style = bold];
	"if (Y)" -> break2 [constraint = false, style = bold];
	"if (Z)" -> {A break1 B} [color = grey];
	{break1 "if (Z)"} -> break2 [color = lightgrey, style = dashed];
	break1 -> B [color = grey];
	break2 -> {C while} [style = bold];
	{rank=same; A break1 B break2}
	{rank=same; "if (Z)" C}
	{rank=same; while D}
	{edge [style=invis];
		A -> break1 -> B -> break2;
	}
}