Not ugly! $,+// (|.10^i.4)*/>:i.6 1296
Linda Sent from AOL Mobile Mail On Wednesday, October 4, 2017 Cliff Reiter <[email protected]> wrote: I was stunned to see how fast, and on pausing, how beautiful Marshall's were. Very unusual and powerful uses of insert. > I doubt you'll find a much faster J solution than: > > ,(+/~10&*)/ 4#,:>:i.6 > > or the uglier but slightly quicker > > ,+// (10<.@^i._4)*/>:i.6 But the problem is structural, not numeric, which attracted me to catalog. On 10/4/2017 6:28 PM, 'Skip Cave' via Programming wrote: > I was stunned by Cliff's cool use of catalog (catalogue?) I had not really > grasped the capabilities of the monadic use of '{' on boxed arguments. I > had always used { dyadically as 'from' > > 2 { 1 2 3 > > 3 > > > This was a revelation: > > > {2#<'123' > > ┌──┬──┬──┐ > > │11│12│13│ > > ├──┼──┼──┤ > > │21│22│23│ > > ├──┼──┼──┤ > > │31│32│33│ > > └──┴──┴──┘ > > > Skip > > > Skip Cave > Cave Consulting LLC > > On Tue, Oct 3, 2017 at 10:21 PM, Cliff Reiter <[email protected]> wrote: > >> A cheat (?) that builds instead of "removing" >> >> z=.,".>{4#<'123456' >> $z >> 1296 >> 10{.z >> 1111 1112 1113 1114 1115 1116 1121 1122 1123 1124 >> >> >> >> On 10/3/2017 4:16 PM, Skip Cave wrote: >> >>> Another interesting Quora problem: >>> >>> Given the integers from 1000 to 9999, remove all integers that contain a >>> 7, >>> 8, 9, or zero, and list the remaining integers. >>> >>> Skip >>> ---------------------------------------------------------------------- >>> For information about J forums see http://www.jsoftware.com/forums.htm >>> >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
