ldsb.hh

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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
 *  Main authors:
 *     Christopher Mears <chris.mears@monash.edu>
 *
 *  Copyright:
 *     Christopher Mears, 2012
 *
 *  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
 *  "Software"), to deal in the Software without restriction, including
 *  without limitation the rights to use, copy, modify, merge, publish,
 *  distribute, sublicense, and/or sell copies of the Software, and to
 *  permit persons to whom the Software is furnished to do so, subject to
 *  the following conditions:
 *
 *  The above copyright notice and this permission notice shall be
 *  included in all copies or substantial portions of the Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

#ifndef __GECODE_INT_LDSB_HH__
#define __GECODE_INT_LDSB_HH__

#include <gecode/int.hh>

namespace Gecode { namespace Int { namespace LDSB {

  class Literal {
  public:
    Literal(void);
    Literal(int _var, int _val);

    int _variable;
    int _value;

    bool operator <(const Literal &rhs) const;
  };

  GECODE_INT_EXPORT
  std::pair<int,int>
  findVar(int *indices, unsigned int n_values, unsigned int seq_size, int index);
}}}

namespace Gecode {
  template<>
  class ArrayTraits<ArgArray<VarImpBase*> > {
  public:
    typedef ArgArray<VarImpBase*>     StorageType;
    typedef VarImpBase*               ValueType;
    typedef ArgArray<VarImpBase*>     ArgsType;
  };

  typedef ArgArray<Int::LDSB::Literal> LiteralArgs;
  template<>
  class ArrayTraits<LiteralArgs> {
  public:
    typedef LiteralArgs        StorageType;
    typedef Int::LDSB::Literal ValueType;
    typedef LiteralArgs        ArgsType;
  };
}

namespace Gecode { namespace Int { namespace LDSB {
  class GECODE_INT_EXPORT SymmetryObject {
  public:
    int nrefs;
    SymmetryObject(void);
    virtual ~SymmetryObject(void);
  };
  class GECODE_INT_EXPORT VariableSymmetryObject : public SymmetryObject {
  public:
    VarImpBase** xs;
    int nxs;
    VariableSymmetryObject(ArgArray<VarImpBase*> vars);
    ~VariableSymmetryObject(void);
  };
  class GECODE_INT_EXPORT ValueSymmetryObject : public SymmetryObject {
  public:
    IntSet values;
    ValueSymmetryObject(IntSet vs);
  };
  class GECODE_INT_EXPORT VariableSequenceSymmetryObject : public SymmetryObject {
  public:
    VarImpBase** xs;
    int nxs;
    int seq_size;
    VariableSequenceSymmetryObject(ArgArray<VarImpBase*> vars, int ss);
    ~VariableSequenceSymmetryObject();
  };
  class GECODE_INT_EXPORT ValueSequenceSymmetryObject : public SymmetryObject {
  public:
    IntArgs values;
    int seq_size;
    ValueSequenceSymmetryObject(IntArgs vs, int ss);
  };

  template<class View>
  class SymmetryImp {
  public:
    virtual ArgArray<Literal> symmetric(Literal, const ViewArray<View>&) const = 0;
    virtual void update(Literal) = 0;
    virtual SymmetryImp<View>* copy(Space& home) const = 0;
    virtual size_t dispose(Space& home) = 0;
    virtual ~SymmetryImp(void);
    static void* operator new(size_t s, Space& home);
    static void  operator delete(void*,Space&);
    static void  operator delete(void*);
  };
  template <class View>
  class VariableSymmetryImp : public SymmetryImp<View> {
  protected:
    Support::BitSetOffset<Space> indices;
  public:
    VariableSymmetryImp<View>(Space& home, int* vs, unsigned int n);
    VariableSymmetryImp<View>(Space& home, const VariableSymmetryImp<View>& other);
    virtual size_t dispose(Space& home);
    void update(Literal);
    virtual ArgArray<Literal> symmetric(Literal, const ViewArray<View>&) const;
    SymmetryImp<View>* copy(Space& home) const;
  };
  template <class View>
  class ValueSymmetryImp : public SymmetryImp<View>
  {
  public:
    Support::BitSetOffset<Space> values;
    ValueSymmetryImp<View>(Space& home, int* vs, unsigned int n);
    ValueSymmetryImp<View>(Space& home, const ValueSymmetryImp<View>& other);
    virtual size_t dispose(Space& home);
    void update(Literal);
    virtual ArgArray<Literal> symmetric(Literal, const ViewArray<View>&) const;
    SymmetryImp<View>* copy(Space& home) const;
  };
  template <class View>
  class VariableSequenceSymmetryImp : public SymmetryImp<View>
  {
  protected:
    unsigned int *indices;
    unsigned int n_indices;
    unsigned int seq_size;
    unsigned int n_seqs;

    // e.g. lookup[2] == 10 indicates that the variable with index 2
    // occurs at position 10 in the "indices" array.
    // If a variable occurs more than once, only the first occurrence
    // is recorded.
    // A value of -1 indicates that the variable does not occur in
    // "indices".
    int *lookup;
    unsigned int lookup_size;

    int getVal(unsigned int sequence, unsigned int position) const;
  public:
    VariableSequenceSymmetryImp<View>(Space& home, int *_indices, unsigned int n, unsigned int seqsize);
    VariableSequenceSymmetryImp<View>(Space& home, const VariableSequenceSymmetryImp<View>& s);
    virtual size_t dispose(Space& home);
    void update(Literal);
    virtual ArgArray<Literal> symmetric(Literal, const ViewArray<View>&) const;
    SymmetryImp<View>* copy(Space& home) const;
  };
  template <class View>
  class ValueSequenceSymmetryImp : public SymmetryImp<View>
  {
  protected:
    int *values;
    unsigned int n_values;
    unsigned int seq_size;
    unsigned int n_seqs;
    Support::BitSet<Space> dead_sequences;
    int getVal(unsigned int sequence, unsigned int position) const;
  private:
    ValueSequenceSymmetryImp<View>(const ValueSequenceSymmetryImp<View>&);
  public:
    ValueSequenceSymmetryImp<View>(Space& home, int* _values, unsigned int n, unsigned int seqsize);
    ValueSequenceSymmetryImp<View>(Space& home, const ValueSequenceSymmetryImp<View>& vss);
    virtual size_t dispose(Space& home);
    void update(Literal);
    virtual ArgArray<Literal> symmetric(Literal, const ViewArray<View>&) const;
    SymmetryImp<View>* copy(Space& home) const;
  };

  template<class Val>
  class GECODE_VTABLE_EXPORT LDSBChoice : public PosValChoice<Val> {
  private:
    const Literal * const _literals;
    const int _nliterals;
  public:
    LDSBChoice(const Brancher& b, unsigned int a, const Pos& p, const Val& n,
               const Literal* literals, int nliterals);
    ~LDSBChoice(void);
    const Literal* literals(void) const;
    int nliterals(void) const;
    virtual void archive(Archive& e) const;
  };

  template<class View, int n, class Val, unsigned int a,
           class Filter, class Print>
  class LDSBBrancher : public ViewValBrancher<View,n,Val,a,Filter,Print> {
  public:
    using typename ViewValBrancher<View,n,Val,a,Filter,Print>::Var;
    SymmetryImp<View>** _syms;
    int _nsyms;
    // Position of variable that last choice was created for
    int _prevPos;
  protected:
    LDSBBrancher(Space& home, LDSBBrancher& b);
    LDSBBrancher(Home home,
                 ViewArray<View>& x,
                 ViewSel<View>* vs[n],
                 ValSelCommitBase<View,Val>* vsc,
                 SymmetryImp<View>** syms, int nsyms,
                 BranchFilter<Var> bf,
                 VarValPrint<Var,Val> vvp);
  public:
    virtual const Choice* choice(Space& home);
    virtual const Choice* choice(const Space& home, Archive& e);
    virtual ExecStatus commit(Space& home, const Choice& c, unsigned int b);
    virtual Actor* copy(Space& home);
    virtual size_t dispose(Space& home);
    static void post(Home home,
                     ViewArray<View>& x,
                     ViewSel<View>* vs[n],
                     ValSelCommitBase<View,Val>* vsc,
                     SymmetryImp<View>** syms,
                     int nsyms,
                     BranchFilter<Var> bf,
                     VarValPrint<Var,Val> vvp);
  };

  template<class View, int n, class Val, unsigned int a>
  void postldsbbrancher(Home home,
                        ViewArray<View>& x,
                        ViewSel<View>* vs[n],
                        ValSelCommitBase<View,Val>* vsc,
                        SymmetryImp<View>** syms, int nsyms,
                        BranchFilter<typename View::VarType> bf,
                        VarValPrint<typename View::VarType,Val> vvp);

  template<class View>
  ModEvent prune(Space& home, View x, int v);

}}}

#include <gecode/int/ldsb/brancher.hpp>
#include <gecode/int/ldsb/sym-imp.hpp>

#endif

// STATISTICS: int-branch