[O] How can I convert a org file to a flowchart

[Feng Shu]

Hello:

I have to draw a flowchart with many many nodes (about 500) and less
construct types(only sequence construct and condition construct),

Now I use org file record all the node labels, How can I convert this
org to a flowchar if i use tag and link to record all the construct?


for example:

* A
* B :COND:
* C
* D

to a -> B -> C
         \-> D  


Thanks
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