Another way is to use prefix to eliminate the upper triangular.
({:(=>.)@%])\>:i.10
1 0 0 0 0 0 0 0 0 0
1 1 0 0 0 0 0 0 0 0
1 0 1 0 0 0 0 0 0 0
1 1 0 1 0 0 0 0 0 0
1 0 0 0 1 0 0 0 0 0
1 1 1 0 0 1 0 0 0 0
1 0 0 0 0 0 1 0 0 0
1 1 0 1 0 0 0 1 0 0
1 0 1 0 0 0 0 0 1 0
1 1 0 0 1 0 0 0 0 1
Still have the overhead of having to pad the short rows with zeros but
if other processing is to be done simply do it in the tacit expression
before returning.
([:<]#~{:(=>.)@%])\>:i.10
+-+---+---+-----+---+-------+---+-------+-----+--------+
|1|1 2|1 3|1 2 4|1 5|1 2 3 6|1 7|1 2 4 8|1 3 9|1 2 5 10|
+-+---+---+-----+---+-------+---+-------+-----+--------+
Oleg Kobchenko wrote:
+/+/@((=<.)@% >:@i.)"0 >:i.10
27
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