brancher-merit.hpp

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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
 *  Main author:
 *     Christian Schulte <schulte@gecode.org>
 *
 *  Copyright:
 *     Christian Schulte, 2012
 *
 *  Last modified:
 *     $Date: 2013-02-18 21:53:58 +0100 (Mon, 18 Feb 2013) $ by $Author: schulte $
 *     $Revision: 13310 $
 *
 *  This file is part of Gecode, the generic constraint
 *  development environment:
 *     http://www.gecode.org
 *
 *  Permission is hereby granted, free of charge, to any person obtaining
 *  a copy of this software and associated documentation files (the
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 *  permit persons to whom the Software is furnished to do so, subject to
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namespace Gecode {

  template<class _View, class _Val>
  class MeritBase {
  public:
    typedef _View View;
    typedef _Val Val;
    MeritBase(Space& home, const VarBranch& vb);
    MeritBase(Space& home, bool share, MeritBase& mb);
    bool notice(void) const;
    void dispose(Space& home);
  };

  template<class View>
  class MeritFunction : public MeritBase<View,double> {
  public:
    typedef typename View::VarType Var;
    typedef typename BranchTraits<Var>::Merit Function;
  protected:
    Function f;
  public:
    MeritFunction(Space& home, const VarBranch& vb);
    MeritFunction(Space& home, bool shared, MeritFunction& mf);
    double operator ()(const Space& home, View x, int i);
  };

  template<class View>
  class MeritDegree : public MeritBase<View,unsigned int> {
  public:
    MeritDegree(Space& home, const VarBranch& vb);
    MeritDegree(Space& home, bool shared, MeritDegree& md);
    unsigned int operator ()(const Space& home, View x, int i);
  };

  template<class View>
  class MeritAFC : public MeritBase<View,double> {
  protected:
    AFC afc;    
  public:
    MeritAFC(Space& home, const VarBranch& vb);
    MeritAFC(Space& home, bool shared, MeritAFC& ma);
    double operator ()(const Space& home, View x, int i);
    bool notice(void) const;
    void dispose(Space& home);
  };

  template<class View>
  class MeritActivity : public MeritBase<View,double> {
  protected:
    Activity activity;
  public:
    MeritActivity(Space& home, const VarBranch& vb);
    MeritActivity(Space& home, bool shared, MeritActivity& ma);
    double operator ()(const Space& home, View x, int i);
    bool notice(void) const;
    void dispose(Space& home);
  };


  // Merit base class
  template<class View, class Val>
  forceinline
  MeritBase<View,Val>::MeritBase(Space&, const VarBranch&) {}
  template<class View, class Val>
  forceinline
  MeritBase<View,Val>::MeritBase(Space&, bool, MeritBase&) {}
  template<class View, class Val>
  forceinline bool
  MeritBase<View,Val>::notice(void) const {
    return false;
  }
  template<class View, class Val>
  forceinline void
  MeritBase<View,Val>::dispose(Space&) {}

  // User-defined function merit
  template<class View>
  forceinline
  MeritFunction<View>::MeritFunction(Space& home, const VarBranch& vb)
    : MeritBase<View,double>(home,vb),
      f(function_cast<Function>(vb.merit())) {}
  template<class View>
  forceinline
  MeritFunction<View>::MeritFunction(Space& home, bool shared, 
                                     MeritFunction& mf) 
    : MeritBase<View,double>(home,shared,mf), f(mf.f) {}
  template<class View>
  forceinline double
  MeritFunction<View>::operator ()(const Space& home, View x, int i) {
    typename View::VarType y(x.varimp());
    return f(home,y,i);
  }

  // Degree merit
  template<class View>
  forceinline
  MeritDegree<View>::MeritDegree(Space& home, const VarBranch& vb)
    : MeritBase<View,unsigned int>(home,vb) {}
  template<class View>
  forceinline
  MeritDegree<View>::MeritDegree(Space& home, bool shared, 
                                 MeritDegree& md)
    : MeritBase<View,unsigned int>(home,shared,md) {}
  template<class View>
  forceinline unsigned int
  MeritDegree<View>::operator ()(const Space&, View x, int) {
    return x.degree();
  }

  // AFC merit
  template<class View>
  forceinline
  MeritAFC<View>::MeritAFC(Space& home, const VarBranch& vb)
    : MeritBase<View,double>(home,vb), afc(vb.afc()) {}
  template<class View>
  forceinline
  MeritAFC<View>::MeritAFC(Space& home, bool shared, 
                           MeritAFC& ma)
    : MeritBase<View,double>(home,shared,ma) {
    afc.update(home,shared,ma.afc);
  }
  template<class View>
  forceinline double
  MeritAFC<View>::operator ()(const Space& home, View x, int) {
    return x.afc(home);
  }
  template<class View>
  forceinline bool
  MeritAFC<View>::notice(void) const {
    return true;
  }
  template<class View>
  forceinline void
  MeritAFC<View>::dispose(Space&) {
    afc.~AFC();
  }


  // Acitivity merit
  template<class View>
  forceinline
  MeritActivity<View>::MeritActivity(Space& home, const VarBranch& vb)
    : MeritBase<View,double>(home,vb), activity(vb.activity()) {}
  template<class View>
  forceinline
  MeritActivity<View>::MeritActivity(Space& home, bool shared, 
                                     MeritActivity& ma)
    : MeritBase<View,double>(home,shared,ma) {
    activity.update(home, shared, ma.activity);
  }
  template<class View>
  forceinline double
  MeritActivity<View>::operator ()(const Space&, View, int i) {
    return activity[i];
  }
  template<class View>
  forceinline bool
  MeritActivity<View>::notice(void) const {
    return true;
  }
  template<class View>
  forceinline void
  MeritActivity<View>::dispose(Space&) {
    activity.~Activity();
  }

}

// STATISTICS: kernel-branch