pick=: (56 ?~ 5:) ,&:>: (46 ?~ 1:)
----- Original Message ----- From: Henry Rich <[email protected]> Date: Saturday, August 1, 2009 19:49 Subject: Re: [Jprogramming] Picking lottery tickets To: Programming forum <[email protected]> > Does this suffice? > > pick =: [: >: (56 ?~ 5:) , (46 ?~ 1:) > pick"0 i. 6 > 7 51 48 55 36 19 > 15 16 24 38 51 6 > 55 47 34 4 29 30 > 54 1 53 29 30 42 > 45 15 38 46 39 16 > 25 32 2 51 22 4 > > Henry Rich > > John Randall wrote: > > The Mega Millions lottery requires picking 5 distinct numbers > in the > > range 1-56 and one number in the range 1-46. The verb > pick below > > randomly chooses a lottery ticket, and uses verb ci from > > > > http://www.jsoftware.com/jwiki/Essays/Combination Index > > > > ci=: 4 : 0 " 1 0 > > 'm n'=. x: x > > z=. 0$q=. n > > for_p. (-i.)m do. > > k=. (p,q) lead y > > y=. y-(p!q)-p!q-k > > q=. q-1+k > > z=. z,k > > end. > > z + (i.#z) + |.!.'' +/\z > > ) > > > > lead=: 4 : 0 > > 'm n'=. x: x > > a=. m!n > > p=. n-1 > > q=. m-1 > > while. p>:q do. > > j=. q+<.-:p-q > > s=. (a - m!j) - y > > if. 0 > s do. p=. j-1 > > elseif. 0 < s do. q=. j+1 > > elseif. 1 do. n-j return. end. > > end. > > (n-1)-p > > ) > > > > pick=:3 : '>:(5 56 ci ?5!56),?46' > > > > pick"0 i.5 > > 9 26 30 38 42 30 > > 12 23 29 48 52 24 > > 11 18 21 25 30 9 > > 1 5 14 19 43 12 > > 15 25 35 42 48 6 > > > > I can also do it less elegantly but from first principles as > > > > pick2=:3 : 0 > > a=.0$0 > > while. 5>#a do. a=.~. a, ?56 end. > >> :(/:~ a),?46 > > ) > > > > pick2"0 i.5 > > 2 32 40 45 48 1 > > 7 28 29 35 54 11 > > 1 26 31 41 55 3 > > 3 11 29 41 43 32 > > 12 20 24 27 41 9 > > > > Is there a better way to do it? I can't seem to make > pick tacit, and > > pick2 seems clumsy. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
