all one line,
treetest =: >(((<' ') ('' ,~ ] #~ [ * <:@:#@:])"0 1~ each [: #S:1 {::) , each
<@": S:0) a=: (fac =: 3 : 'q =. q: y if. 1<#q do. (y ; [: fac "0 each y (] ,
%) ([: */ ] {~ # ?~ <.@:-:@:#)) q else. < y end.') 176715
treetest
1767150
189
9
3
3
21
7
3
9350
55
5
11
170
17
10
2
5
": ,. a
┌────────────────────────────────────────────┐
│1767150 │
├────────────────────────────────────────────┤
│┌───┬───────────┬────────────┐ │
││189│┌─┬───┬───┐│┌──┬───┬───┐│ │
││ ││9│┌─┐│┌─┐│││21│┌─┐│┌─┐││ │
││ ││ ││3│││3││││ ││7│││3│││ │
││ ││ │└─┘│└─┘│││ │└─┘│└─┘││ │
││ │└─┴───┴───┘│└──┴───┴───┘│ │
│└───┴───────────┴────────────┘ │
├────────────────────────────────────────────┤
│┌────┬─────────────┬───────────────────────┐│
││9350│┌──┬───┬────┐│┌───┬────┬────────────┐││
││ ││55│┌─┐│┌──┐│││170│┌──┐│┌──┬───┬───┐│││
││ ││ ││5│││11││││ ││17│││10│┌─┐│┌─┐││││
││ ││ │└─┘│└──┘│││ │└──┘││ ││2│││5│││││
││ │└──┴───┴────┘││ │ ││ │└─┘│└─┘││││
││ │ ││ │ │└──┴───┴───┘│││
││ │ │└───┴────┴────────────┘││
│└────┴─────────────┴───────────────────────┘│
└────────────────────────────────────────────┘
The challenge is how to recreate a, from treetest. I think a is the "right
format" for a tree representation, and this has applications in parsing code
blocks and dsls like html and python.
Here is a link to Raul's excellent code from years ago:
http://www.jsoftware.com/pipermail/programming/2007-April/005908.html
but here is an approach that seems simple, except that it is hard to generalize:
tree =: ((([: >: [: <./ #S:1@:{::) = #S:1@:{::) <;.1 ])
tree2 =: > L:1 @:({. , tree)
tree2 each each tree2 each tree2 ". leaf <^:(2 %~ 0 i.~' '=]) "1 treetest
This is almost identical to a (first term extra boxed), but doing an extra
"tree" level would require calling tree2 each each each.
Is there a way to generalize a solution here?
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