/* 

  Giapetto's problem in Picat.

  From the article
  "The GNU Linear Programming Kit, Part 1: Introduction to linear optimization"
  http://www-128.ibm.com/developerworks/library/l-glpk1/index.html?ca=drs-
  
  (Translation of the GLPK MathProg model.)

  This finds the optimal solution for maximizing Giapetto's profit.
  
  

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

*/


% import util.
import cp.


main => go.


go =>
  
  % Decision variables
  % X1 :: 0..100, % soldier
  % X2 :: 0..100, % train 

  % Objective function (Giapetto's profit, to maximize)
  Z #= 3*X1 + 2*X2,


  X1 #>= 0,
  X2 #>= 0,

  2*X1 + X2 #<= 100, % Finishing 
  X1 + X2 #<= 80,    % Carpentry
  X1 #<= 40,        % Demand

  solve($[max(Z)], [X1,X2]),

  println(x1=X1),
  println(x2=X2),

  nl.