Graphviz如何控制边

。我在找右边的图，但我得到的是左边的图。我对Graphviz不熟悉。我还必须制作节点1和节点2，因为我无法模拟右侧的图像。我的终端形状也不完全一样。谁来帮帮我。我的代码到现在为止：

digraph M
{
  style=filled;
  graph [splines = headport];

  START->1
  1->"Is COUNT\nan even\nnumber?"
  "Is COUNT\nan even\nnumber?"->"SUM = SUM +\nCOUNT" [label=TRUE]
  "SUM = SUM +\nCOUNT"->2
  "Is COUNT\nan even\nnumber?"->2 [label=FALSE]
  2->"COUNT = COUNT+1"
  "COUNT = COUNT+1"->"IS COUNT >\n20"
  "IS COUNT >\n20"->1 [label=FALSE]
  "IS COUNT >\n20"->STOP[label=TRUE]


  "Is COUNT\nan even\nnumber?"[shape=diamond]
  "SUM = SUM +\nCOUNT"[shape=rectangle]
  "IS COUNT >\n20"[shape=diamond]
  "COUNT = COUNT+1"[shape=rectangle]
  1[shape=circle]
  2[shape=circle]
  START[shape=record, style="rounded"]
  STOP[shape=record, style="rounded"]
}

---

我对您的图表做了一些更改，以使您更接近。样条曲线的多段线，并将1和2节点的属性更改为更接近目标。显然不完美，但希望更好，足以帮助和建议其他方法，您可以进一步改进它，而无需进行重大重新设计

digraph M
{
  style=filled;
  graph [splines = headport splines=polyline];

  START->1
  1->"Is COUNT\nan even\nnumber?"
  "Is COUNT\nan even\nnumber?"->"SUM = SUM +\nCOUNT" [label=TRUE]
  "SUM = SUM +\nCOUNT"->2
  "Is COUNT\nan even\nnumber?"->2 [label=FALSE]
  2->"COUNT = COUNT+1" 
  "COUNT = COUNT+1"->"IS COUNT >\n20"
  "IS COUNT >\n20"->1 [label=FALSE tailport=e]
  "IS COUNT >\n20"->STOP[label=TRUE ]


  "Is COUNT\nan even\nnumber?"[shape=diamond]
  "SUM = SUM +\nCOUNT"[shape=rectangle]
  "IS COUNT >\n20"[shape=diamond]
  "COUNT = COUNT+1"[shape=rectangle headport=n]
  1[shape=point size="0,0" label=""]
  2[shape=point size="0,0" label=""]
  START[shape=record, style="rounded"]
  STOP[shape=record, style="rounded"]
}