problem.h

/***************************************************************************
 *   Copyright (C) Anders Larsen                                           *
 *   anders.larsen@spray.se                                                *
 *                                                                         *
 *   Use of a Genetic Algoritm to solve a Traveling Salesman Problem.      *
 *   The code can easily be adapted to other types problems as long as     *
 *   solutions  can be expressed as fixed length arrays of integers.       *
 *                                                                         *
 *   This program 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 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program 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 this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

// This file contains a base class for some problem to solve using the GA.
// A problem must define how to encode, mutate, crossover and evaluate
// solutions. Solutions are stored as vectors of ints.

#ifndef PROBLEM_H
#define PROBLEM_H

#include <vector>

// A Solution is a vector of ints
typedef std::vector<int> Sol;
typedef std::vector<int>::iterator SolIter;

// Genetic operations depend on the problem type
class Problem {
private:
public:
   // Generate a random valid solution &s
   virtual void encode(Sol &s) = 0;

   // Mutate the soultion &s
   virtual void mutate(Sol &s) = 0;

   // Use old genes in a and b to create new in c and d
   virtual void crossover(const Sol &a, const Sol &b, Sol &c, Sol &d) = 0;

   // Calculate cost for solution &s
   virtual double evaluate(Sol &s) = 0;
};
//---------------------------------------------------------------------------

#endif