bin-packing.hh

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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
 *  Main authors:
 *     Christian Schulte <schulte@gecode.dev>
 *
 *  Contributing authors:
 *     Fabio Tardivo <ftardivo@nmsu.edu>
 *     Stefano Gualandi <stefano.gualandi@gmail.com>
 *
 *  Copyright:
 *     Fabio Tardivo, 2024
 *     Stefano Gualandi, 2013
 *     Christian Schulte, 2010
 *
 *  This file is part of Gecode, the generic constraint
 *  development environment:
 *     http://www.gecode.dev
 *
 *  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_BIN_PACKING_HH
#define GECODE_INT_BIN_PACKING_HH
 
#include <gecode/int.hh>

 
namespace Gecode { namespace Int { namespace BinPacking {

  class Item : public DerivedView<IntView> {
  protected:
    using DerivedView<IntView>::x;
    int s;
  public:
    Item(void);
    Item(IntView b, int s);

    IntView bin(void) const;
    void bin(IntView b);
    int size(void) const;
    void size(int s);

    void update(Space& home, Item& i);
  };

  bool operator ==(const Item& i, const Item& j);
  bool operator !=(const Item& i, const Item& j);

  bool operator <(const Item& i, const Item& j);
 

  class SizeSet {
  protected:
    int n;
    int t;
    int* s;
  public:
    SizeSet(void);
    SizeSet(Region& region, int n_max);
    void add(int s);
    int card(void) const;
    int total(void) const;
    int operator [](int i) const;
  };

  class SizeSetMinusOne : public SizeSet {
  protected:
    int p;
  public:
    SizeSetMinusOne(void);
    SizeSetMinusOne(Region& region, int n);
    void minus(int s);
    int card(void) const;
    int total(void) const;
    int operator [](int i) const;
  };

  struct LambdaRange {
    int min;
    int max;
  };

  class Pack : public Propagator {
  protected:
    ViewArray<OffsetView> l;
    ViewArray<Item> bs;
    IntPropLevel ipl;
    int t;
    Pack(Home home, ViewArray<OffsetView>& l, ViewArray<Item>& bs,
         IntPropLevel ipl);
    Pack(Space& home, Pack& p);
  public:
    GECODE_INT_EXPORT
    static ExecStatus post(Home home,
                           ViewArray<OffsetView>& l, ViewArray<Item>& bs,
                           IntPropLevel ipl=IPL_DEF);
    template<class SizeSet>
    bool nosum(const SizeSet& s, int a, int b, int& ap, int& bp);
    template<class SizeSet>
    bool nosum(const SizeSet& s, int a, int b);
    GECODE_INT_EXPORT
    virtual ExecStatus propagate(Space& home, const ModEventDelta& med);
    GECODE_INT_EXPORT
    virtual PropCost cost(const Space& home, const ModEventDelta& med) const;
    GECODE_INT_EXPORT
    virtual void reschedule(Space& home);
    GECODE_INT_EXPORT
    virtual Actor* copy(Space& home);
    virtual size_t dispose(Space& home);
    static int const n_reductions = 3;
    static void calc_reductions(const ViewArray<Item>& bs,
                                const ViewArray<OffsetView>& l,
                                int* weights_base_reduction,
                                int& capacity_base_reduction,
                                int* delta_reductions);
    static int f_ccm1(int w, int l, int c);
    static int f_mt(int w, int l, int c);
    static int f_bj1(int w, int l, int c);
    static int f_vb2_base(int w, int l, int c);
    static int f_vb2(int w, int l, int c);
    static int f_fs1(int w, int l, int c);
    static int f_rad2_base(int w, int l, int c);
    static int f_rad2(int w, int l, int c);
    static int const n_lambda_samples = 256;
    static LambdaRange l_ccm1(int c);
    static LambdaRange l_mt(int c);
    static LambdaRange l_bj1(int c);
    static LambdaRange l_vb2(int c);
    static LambdaRange l_fs1(int c);
    static LambdaRange l_rad2(int c);
    static LambdaRange sanitize_lambda_range(LambdaRange lambda,
                                             int n_weights, int max_weight);
    template<int f(int,int,int)>
    static int calc_dff_lower_bound_single_lambda(const int* weights,
                                                  int n_weights,
                                                  int capacity, int lambda);
    template<int f(int,int,int), LambdaRange l(int)>
    static int calc_dff_lower_bound(const int* weights, int n_weights,
                                    int capacity, int n_not_zero_weights,
                                    int max_weight, bool sanitize = false);
  };
 

  class ConflictGraph {
  protected:
    Home& home;
    const IntVarArgs& b;
    unsigned int bins;
    int nodes(void) const;

    class NodeSet : public Support::RawBitSetBase {
    public:
      NodeSet(void);
      NodeSet(Region& r, int n);
      NodeSet(Region& r, int n, const NodeSet& ns);
      void allocate(Region& r, int n);
      void init(Region& r, int n);
      bool in(int i) const;
      void incl(int i);
      void excl(int i);
      void copy(int n, const NodeSet& ns);
      void empty(int n);
      static bool iwn(NodeSet& iwa, const NodeSet& a,
                      NodeSet& iwb, const NodeSet& b,
                      const NodeSet& c, int n);
    };

    class Node {
    public:
      NodeSet n;
      unsigned int d;
      unsigned int w;
      Node(void);
    };

    Node* node;

    class Nodes {
    private:
      const NodeSet& ns;
      unsigned int c;
    public:
      Nodes(const NodeSet& ns);


      void operator ++(void);



      int operator ()(void) const;
    };



    class Clique {
    public:
      NodeSet n;
      unsigned int c;
      unsigned int w;
      Clique(Region& r, int m);
      void incl(int i, unsigned int w);
      void excl(int i, unsigned int w);
    };

    int pivot(const NodeSet& a, const NodeSet& b) const;
    GECODE_INT_EXPORT
    ExecStatus bk(NodeSet& p, NodeSet& x);



    Clique cur;
    Clique max;
    ExecStatus clique(void);
    ExecStatus clique(int i);
    ExecStatus clique(int i, int j);
    ExecStatus clique(int i, int j, int k);
  public:
    ConflictGraph(Home& home, Region& r, const IntVarArgs& b,
                  int m);
    void edge(int i, int j, bool add=true);
    bool adjacent(int i, int j) const;
    ExecStatus post(void);
    IntSet maxclique(void) const;
    ~ConflictGraph(void);
  };
 
}}}
 
#include <gecode/int/bin-packing/propagate.hpp>
#include <gecode/int/bin-packing/conflict-graph.hpp>
 
#endif
 
// STATISTICS: int-prop