/* 

  Satisfication problem in Picat.

  From the Alma-0 model satisfy.a0
  (http://www.cwi.nl/en/alma)
  """
  The problem is to generate all interpretations that satisfy a given 
  propositional formula.
  """

  There are 6 solutions:
    [0,0,1,1]
    [0,1,1,1]
    [1,0,1,1]
    [1,1,0,0]
    [1,1,0,1]
    [1,1,1,0]

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

*/

import cp.

main => go.

go =>
  
  N = 4,

  X = new_list(N),
  X :: 0..1,

  (X[1] #= 1 #/\ X[2] #= 1) #\/ (X[3] #= 1 #/\ X[4] #= 1),
  (X[1] #!= X[3]) #\/ (X[2] #!= X[4]),

  solve(X),

  println(X),
  fail,

  
  nl.