What about using some Maths? E.g. (*>:)@-:42 462 Mike Please reply to [email protected]. Sent from my iPad
> On 28 Aug 2017, at 18:12, Raul Miller <[email protected]> wrote: > > Well... the simplest J implementation for that problem would be: > > 462 > 462 > > But there are other ways of getting that result: > > +/(* 0 = 2&|)1+i.42 > 462 > +/(* 0 = 2&|)i.43 > 462 > +/2*i.>:-:42 > 462 > +/2*1+i.21 > 462 > +/2*i.22 > 462 > > and... so on... > > I suppose a part of the question is: what is acceptable, to the > audience, to do outside the computer implementation? (Which, in turn, > can lead to forbidding all languages except the one preferred by a > specific person, among other things.) > > Thanks, > > -- > Raul > >> On Mon, Aug 28, 2017 at 1:02 PM, Skip Cave <[email protected]> wrote: >> A simple problem posted on Quora: >> >> What is the sum of all the even numbers from 2 to 42? >> >> My J solution: >> a=:>:i.42 >> +/(-.2|a)#a >> 462 >> >> I'm sure this can be done in a single line using a hook or fork. >> but I'm not clear enough with the train rules to put this all together >> on a single line. >> Any suggestions? >> >> >> >> >> >> Skip Cave >> Cave Consulting LLC >> ---------------------------------------------------------------------- >> 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
