/* 

  Largest proper divisor of n (Rosetta code) in Picat.

  http://rosettacode.org/wiki/Largest_proper_divisor_of_n
  """
  a(1) = 1; for n > 1, a(n) = largest proper divisor of n, where n < 101 .
  """

  This program was created by Hakan Kjellerstrand, hakank@gmail.com
  See also my Picat page: http://www.hakank.org/picat/

*/

main => go.

go ?=>
  foreach(I in 1..100)
    printf("%2d%s",a(I), cond(I mod 10 == 0,"\n", " "))
  end,
  nl.


a(1) = 1.
a(N) = Div =>
  a(N,N//2,Div).

a(N,I,I) :-
  N mod I == 0.
a(N,I,Div) :-
  a(N,I-1,Div).