/*******************************************************************************
 * This file is part of OscaR (Scala in OR).
 *   
 * OscaR is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2.1 of the License, or
 * (at your option) any later version.
 * 
 * OscaR is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License along with OscaR.
 * If not, see http://www.gnu.org/licenses/gpl-3.0.html
 ******************************************************************************/
package oscar.examples.cp.hakank

import oscar.cp.modeling._

import oscar.cp.core._
import scala.io.Source._
import scala.math._

/*

  Just forgotten puzzle (Enigma 1517) in Oscar.

  From http://www.f1compiler.com/samples/Enigma 201517.f1.html
  """
  Enigma 1517 Bob Walker, New Scientist magazine, October 25, 2008.

  Joe was furious when he forgot one of his bank account numbers.
  He remembered that it had all the digits 0 to 9 in some order,
  so he tried the following four sets without success:

  9 4 6 2 1 5 7 8 3 0
  8 6 0 4 3 9 1 2 5 7
  1 6 4 0 2 9 7 8 5 3
  6 8 2 4 3 1 9 0 7 5

  When Joe finally remembered his account number, he realised that
  in each set just four of the digits were in their correct position
  and that, if one knew that, it was possible to work out his
  account number. What was it?
  """
  
  @author Hakan Kjellerstrand hakank@gmail.com
  http://www.hakank.org/oscar/
 
*/

object JustForgotten {

  def main(args: Array[String]) {

    val cp = CPSolver()

    //
    // data
    //
    val rows = 4
    val cols = 10

    // The four tries
    val a = Array(Array(9,4,6,2,1,5,7,8,3,0),
                  Array(8,6,0,4,3,9,1,2,5,7),
                  Array(1,6,4,0,2,9,7,8,5,3),
                  Array(6,8,2,4,3,1,9,0,7,5))
    
    //
    // variables
    // 
    val x = Array.fill(cols)(CPVarInt(cp, 0 to 9))

    //
    // constraints
    //
    var numSols = 0

    cp.solve subjectTo {

      cp.add(allDifferent(x), Strong)
      for(r <- 0 until rows) {
        cp.add(sum(for{c <- 0 until cols} yield x(c) === a(r)(c)) == 4)
      }


    } exploration {
       
      cp.binary(x)

      println("\nSolution:")
      println("x: " + x.mkString(""))
      println("\nThe four tries, where '!' represents a correct digit:")
      for(i <- 0 until rows) {
        for(j <- 0 until cols) {
          var c = " ";
          if (a(i)(j) == x(j).value) {
            c = "!";
          }
          print(a(i)(j) + c + " ")
        }
        println()
      }

      numSols += 1

   } run()

    println("\nIt was " + numSols + " solutions.")
    cp.printStats()

  }

}