crypta.cs

//
// Copyright 2012 Hakan Kjellerstrand
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

using System;
using Google.OrTools.ConstraintSolver;

public class Crypta
{
  /**
   *
   * Cryptarithmetic puzzle.
   * 
   * Prolog benchmark problem GNU Prolog (crypta.pl)
   * """
   * Name           : crypta.pl
   * Title          : crypt-arithmetic
   * Original Source: P. Van Hentenryck's book
   * Adapted by     : Daniel Diaz - INRIA France
   * Date           : September 1992
   *
   * Solve the operation:
   *
   *    B A I J J A J I I A H F C F E B B J E A
   *  + D H F G A B C D I D B I F F A G F E J E
   *  -----------------------------------------
   *  = G J E G A C D D H F A F J B F I H E E F
   * """
   *
   *
   * Also see http://hakank.org/or-tools/crypta.py
   *
   */
  private static void Solve()
  {
    Solver solver = new Solver("Crypta");

    //
    // Decision variables
    //
    IntVar A = solver.MakeIntVar(0, 9, "A");
    IntVar B = solver.MakeIntVar(0, 9, "B");
    IntVar C = solver.MakeIntVar(0, 9, "C");
    IntVar D = solver.MakeIntVar(0, 9, "D");
    IntVar E = solver.MakeIntVar(0, 9, "E");
    IntVar F = solver.MakeIntVar(0, 9, "F");
    IntVar G = solver.MakeIntVar(0, 9, "G");
    IntVar H = solver.MakeIntVar(0, 9, "H");
    IntVar I = solver.MakeIntVar(0, 9, "I");
    IntVar J = solver.MakeIntVar(0, 9, "J");

    IntVar[] LD = new IntVar[] {A,B,C,D,E,F,G,H,I,J};
    
    IntVar Sr1 = solver.MakeIntVar(0, 1, "Sr1");
    IntVar Sr2 = solver.MakeIntVar(0, 1, "Sr2");


    //
    // Constraints
    //
    solver.Add(LD.AllDifferent());
    solver.Add(B >= 1);
    solver.Add(D >= 1);
    solver.Add(G >= 1);

    solver.Add((A+10*E+100*J+1000*B+10000*B+100000*E+1000000*F+
                E+10*J+100*E+1000*F+10000*G+100000*A+1000000*F) ==
               (F+10*E+100*E+1000*H+10000*I+100000*F+1000000*B+10000000*Sr1));


    solver.Add((C+10*F+100*H+1000*A+10000*I+100000*I+1000000*J+
                F+10*I+100*B+1000*D+10000*I+100000*D+1000000*C+Sr1) ==
               (J+10*F+100*A+1000*F+10000*H+100000*D+1000000*D+10000000*Sr2));


    solver.Add((A+10*J+100*J+1000*I+10000*A+100000*B+
                B+10*A+100*G+1000*F+10000*H+100000*D+Sr2) ==
               (C+10*A+100*G+1000*E+10000*J+100000*G));

    //
    // Search
    //
    DecisionBuilder db = solver.MakePhase(LD,
                                          Solver.INT_VAR_DEFAULT,
                                          Solver.INT_VALUE_DEFAULT);

    solver.NewSearch(db);

    while (solver.NextSolution()) {
      for(int i = 0; i < 10; i++) {
        Console.Write(LD[i].ToString() + " ");
      }
      Console.WriteLine();
    }

    Console.WriteLine("\nWallTime: " + solver.WallTime() + "ms ");
    Console.WriteLine("Failures: " + solver.Failures());
    Console.WriteLine("Branches: " + solver.Branches());

    solver.EndSearch();

  }

  public static void Main(String[] args)
  {
    Solve();
  }
}