/* 

  Global constraint cond_lex_cost in Picat.

  From Global Constraint Catalogue
  http://www.emn.fr/x-info/sdemasse/gccat/Ccond_lex_cost.html
  """
  cond_lex_cost(VECTOR,  PREFERENCE_TABLE, COST)
  
  Purpose

  VECTOR is assigned to the COSTth item of the collection PREFERENCE_TABLE.
  
  Example
      (
      <0, 1>,
      <
      tuple-〈1, 0>,
      tuple-〈0, 1>,
      tuple-〈0, 0>,
      tuple-〈1, 1>
      >, 2
      )
  
  The cond_lex_cost constraint holds since VECTOR is assigned to the 
  second item of the collection PREFERENCE_TABLE.
  """


  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 = 4,
  M = 2,

  Arr = new_array(N,M),
  Arr :: 0..1,

  V1 = new_list(M),
  V1 :: 0..1,

  Pos :: 1..N,

  % V1 = [0,1],
  Arr = {{1,0},
         {0,1},
         {0,0},
         {1,1}},

  cond_lex_cost(V1, Arr, Pos),

  Vars = Arr.vars ++ V1 ++ [Pos],
  solve(Vars),

  println(arr=Arr),
  println(v1=V1),
  println(pos=Pos),
  nl,
  fail,
  
  nl.

go => true.

%
% Instead of COST, I call the third parameter Ix (position).
%
cond_lex_cost(V, A, Ix) =>
   member(I,1..A.len),
   Ix #= I,
   foreach(J in 1..V.len) 
     A[I,J] #= V[J]
   end.