/* 

  Global constraint arith_or in Picat.

  From Global Constraint Catalogue
  http://www.emn.fr/x-info/sdemasse/gccat/Carith_or.html
  """
  Enforce for all pairs of variables var1i,<U+200B>var2i of the 
  VARIABLES1 and VARIABLES2 collections to have var1i 
  RELOP VALUE∨var2i RELOP VALUE.
  
  Example
      (
      〈0,1,0,0,1〉,
      〈0,0,0,1,0〉,=,0
      )
  
  The constraint arith_or holds since, for all pairs of variables 
  var1i,var2i of the VARIABLES1 and VARIABLES2 collections, there is 
  at least one variable that is equal to 0.
  """ 

  Cf http://hakank.org/picat/arith.pi (for global constraint arith)


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

*/


import cp.


main => go.


go ?=>

  N = 5,

  X = new_list(N),
  X :: 0..2,
  Y = new_list(N),
  Y :: 0..2,
  
  Z :: 0..9,

  % X = [0,1,0,0,1],
  % Y = [0,0,0,1,0],
  arith_or(X, Y, #=, Z),
  % Z #= 1,

  Vars = X ++ Y ++ [Z],
  solve(Vars),
  
  println(x=X),
  println(y=Y),
  println(z=Z),    
  nl,
  
  fail,

  nl.

go => true.

arith_or(X, Y, Relop, Val) =>
  foreach(I in 1..X.len)
    call(Relop,XVal,X[I]),
    call(Relop,YVal,Y[I]),    
    XVal #= Val #\/ YVal #= Val
  end.