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Differential D5594 Diff 18104 extern/quadriflow/3rd/lemon-1.3.1/lemon/hypercube_graph.h

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extern/quadriflow/3rd/lemon-1.3.1/lemon/hypercube_graph.h

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/* -*- mode: C++; indent-tabs-mode: nil; -*-
*
* This file is a part of LEMON, a generic C++ optimization library.
*
* Copyright (C) 2003-2009
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
* (Egervary Research Group on Combinatorial Optimization, EGRES).
*
* Permission to use, modify and distribute this software is granted
* provided that this copyright notice appears in all copies. For
* precise terms see the accompanying LICENSE file.
*
* This software is provided "AS IS" with no warranty of any kind,
* express or implied, and with no claim as to its suitability for any
* purpose.
*
*/
#ifndef HYPERCUBE_GRAPH_H
#define HYPERCUBE_GRAPH_H
#include <vector>
#include <lemon/core.h>
#include <lemon/assert.h>
#include <lemon/bits/graph_extender.h>
///\ingroup graphs
///\file
///\brief HypercubeGraph class.
namespace lemon {
class HypercubeGraphBase {
public:
typedef HypercubeGraphBase Graph;
class Node;
class Edge;
class Arc;
public:
HypercubeGraphBase() {}
protected:
void construct(int dim) {
LEMON_ASSERT(dim >= 1, "The number of dimensions must be at least 1.");
_dim = dim;
_node_num = 1 << dim;
_edge_num = dim * (1 << (dim-1));
}
public:
typedef True NodeNumTag;
typedef True EdgeNumTag;
typedef True ArcNumTag;
int nodeNum() const { return _node_num; }
int edgeNum() const { return _edge_num; }
int arcNum() const { return 2 * _edge_num; }
int maxNodeId() const { return _node_num - 1; }
int maxEdgeId() const { return _edge_num - 1; }
int maxArcId() const { return 2 * _edge_num - 1; }
static Node nodeFromId(int id) { return Node(id); }
static Edge edgeFromId(int id) { return Edge(id); }
static Arc arcFromId(int id) { return Arc(id); }
static int id(Node node) { return node._id; }
static int id(Edge edge) { return edge._id; }
static int id(Arc arc) { return arc._id; }
Node u(Edge edge) const {
int base = edge._id & ((1 << (_dim-1)) - 1);
int k = edge._id >> (_dim-1);
return ((base >> k) << (k+1)) | (base & ((1 << k) - 1));
}
Node v(Edge edge) const {
int base = edge._id & ((1 << (_dim-1)) - 1);
int k = edge._id >> (_dim-1);
return ((base >> k) << (k+1)) | (base & ((1 << k) - 1)) | (1 << k);
}
Node source(Arc arc) const {
return (arc._id & 1) == 1 ? u(arc) : v(arc);
}
Node target(Arc arc) const {
return (arc._id & 1) == 1 ? v(arc) : u(arc);
}
typedef True FindEdgeTag;
typedef True FindArcTag;
Edge findEdge(Node u, Node v, Edge prev = INVALID) const {
if (prev != INVALID) return INVALID;
int d = u._id ^ v._id;
int k = 0;
if (d == 0) return INVALID;
for ( ; (d & 1) == 0; d >>= 1) ++k;
if (d >> 1 != 0) return INVALID;
return (k << (_dim-1)) | ((u._id >> (k+1)) << k) |
(u._id & ((1 << k) - 1));
}
Arc findArc(Node u, Node v, Arc prev = INVALID) const {
Edge edge = findEdge(u, v, prev);
if (edge == INVALID) return INVALID;
int k = edge._id >> (_dim-1);
return ((u._id >> k) & 1) == 1 ? edge._id << 1 : (edge._id << 1) | 1;
}
class Node {
friend class HypercubeGraphBase;
protected:
int _id;
Node(int id) : _id(id) {}
public:
Node() {}
Node (Invalid) : _id(-1) {}
bool operator==(const Node node) const {return _id == node._id;}
bool operator!=(const Node node) const {return _id != node._id;}
bool operator<(const Node node) const {return _id < node._id;}
};
class Edge {
friend class HypercubeGraphBase;
friend class Arc;
protected:
int _id;
Edge(int id) : _id(id) {}
public:
Edge() {}
Edge (Invalid) : _id(-1) {}
bool operator==(const Edge edge) const {return _id == edge._id;}
bool operator!=(const Edge edge) const {return _id != edge._id;}
bool operator<(const Edge edge) const {return _id < edge._id;}
};
class Arc {
friend class HypercubeGraphBase;
protected:
int _id;
Arc(int id) : _id(id) {}
public:
Arc() {}
Arc (Invalid) : _id(-1) {}
operator Edge() const { return _id != -1 ? Edge(_id >> 1) : INVALID; }
bool operator==(const Arc arc) const {return _id == arc._id;}
bool operator!=(const Arc arc) const {return _id != arc._id;}
bool operator<(const Arc arc) const {return _id < arc._id;}
};
void first(Node& node) const {
node._id = _node_num - 1;
}
static void next(Node& node) {
--node._id;
}
void first(Edge& edge) const {
edge._id = _edge_num - 1;
}
static void next(Edge& edge) {
--edge._id;
}
void first(Arc& arc) const {
arc._id = 2 * _edge_num - 1;
}
static void next(Arc& arc) {
--arc._id;
}
void firstInc(Edge& edge, bool& dir, const Node& node) const {
edge._id = node._id >> 1;
dir = (node._id & 1) == 0;
}
void nextInc(Edge& edge, bool& dir) const {
Node n = dir ? u(edge) : v(edge);
int k = (edge._id >> (_dim-1)) + 1;
if (k < _dim) {
edge._id = (k << (_dim-1)) |
((n._id >> (k+1)) << k) | (n._id & ((1 << k) - 1));
dir = ((n._id >> k) & 1) == 0;
} else {
edge._id = -1;
dir = true;
}
}
void firstOut(Arc& arc, const Node& node) const {
arc._id = ((node._id >> 1) << 1) | (~node._id & 1);
}
void nextOut(Arc& arc) const {
Node n = (arc._id & 1) == 1 ? u(arc) : v(arc);
int k = (arc._id >> _dim) + 1;
if (k < _dim) {
arc._id = (k << (_dim-1)) |
((n._id >> (k+1)) << k) | (n._id & ((1 << k) - 1));
arc._id = (arc._id << 1) | (~(n._id >> k) & 1);
} else {
arc._id = -1;
}
}
void firstIn(Arc& arc, const Node& node) const {
arc._id = ((node._id >> 1) << 1) | (node._id & 1);
}
void nextIn(Arc& arc) const {
Node n = (arc._id & 1) == 1 ? v(arc) : u(arc);
int k = (arc._id >> _dim) + 1;
if (k < _dim) {
arc._id = (k << (_dim-1)) |
((n._id >> (k+1)) << k) | (n._id & ((1 << k) - 1));
arc._id = (arc._id << 1) | ((n._id >> k) & 1);
} else {
arc._id = -1;
}
}
static bool direction(Arc arc) {
return (arc._id & 1) == 1;
}
static Arc direct(Edge edge, bool dir) {
return Arc((edge._id << 1) | (dir ? 1 : 0));
}
int dimension() const {
return _dim;
}
bool projection(Node node, int n) const {
return static_cast<bool>(node._id & (1 << n));
}
int dimension(Edge edge) const {
return edge._id >> (_dim-1);
}
int dimension(Arc arc) const {
return arc._id >> _dim;
}
static int index(Node node) {
return node._id;
}
Node operator()(int ix) const {
return Node(ix);
}
private:
int _dim;
int _node_num, _edge_num;
};
typedef GraphExtender<HypercubeGraphBase> ExtendedHypercubeGraphBase;
/// \ingroup graphs
///
/// \brief Hypercube graph class
///
/// HypercubeGraph implements a special graph type. The nodes of the
/// graph are indexed with integers having at most \c dim binary digits.
/// Two nodes are connected in the graph if and only if their indices
/// differ only on one position in the binary form.
/// This class is completely static and it needs constant memory space.
/// Thus you can neither add nor delete nodes or edges, however,
/// the structure can be resized using resize().
///
/// This type fully conforms to the \ref concepts::Graph "Graph concept".
/// Most of its member functions and nested classes are documented
/// only in the concept class.
///
/// This class provides constant time counting for nodes, edges and arcs.
///
/// \note The type of the indices is chosen to \c int for efficiency
/// reasons. Thus the maximum dimension of this implementation is 26
/// (assuming that the size of \c int is 32 bit).
class HypercubeGraph : public ExtendedHypercubeGraphBase {
typedef ExtendedHypercubeGraphBase Parent;
public:
/// \brief Constructs a hypercube graph with \c dim dimensions.
///
/// Constructs a hypercube graph with \c dim dimensions.
HypercubeGraph(int dim) { construct(dim); }
/// \brief Resizes the graph
///
/// This function resizes the graph. It fully destroys and
/// rebuilds the structure, therefore the maps of the graph will be
/// reallocated automatically and the previous values will be lost.
void resize(int dim) {
Parent::notifier(Arc()).clear();
Parent::notifier(Edge()).clear();
Parent::notifier(Node()).clear();
construct(dim);
Parent::notifier(Node()).build();
Parent::notifier(Edge()).build();
Parent::notifier(Arc()).build();
}
/// \brief The number of dimensions.
///
/// Gives back the number of dimensions.
int dimension() const {
return Parent::dimension();
}
/// \brief Returns \c true if the n'th bit of the node is one.
///
/// Returns \c true if the n'th bit of the node is one.
bool projection(Node node, int n) const {
return Parent::projection(node, n);
}
/// \brief The dimension id of an edge.
///
/// Gives back the dimension id of the given edge.
/// It is in the range <tt>[0..dim-1]</tt>.
int dimension(Edge edge) const {
return Parent::dimension(edge);
}
/// \brief The dimension id of an arc.
///
/// Gives back the dimension id of the given arc.
/// It is in the range <tt>[0..dim-1]</tt>.
int dimension(Arc arc) const {
return Parent::dimension(arc);
}
/// \brief The index of a node.
///
/// Gives back the index of the given node.
/// The lower bits of the integer describes the node.
static int index(Node node) {
return Parent::index(node);
}
/// \brief Gives back a node by its index.
///
/// Gives back a node by its index.
Node operator()(int ix) const {
return Parent::operator()(ix);
}
/// \brief Number of nodes.
int nodeNum() const { return Parent::nodeNum(); }
/// \brief Number of edges.
int edgeNum() const { return Parent::edgeNum(); }
/// \brief Number of arcs.
int arcNum() const { return Parent::arcNum(); }
/// \brief Linear combination map.
///
/// This map makes possible to give back a linear combination
/// for each node. It works like the \c std::accumulate function,
/// so it accumulates the \c bf binary function with the \c fv first
/// value. The map accumulates only on that positions (dimensions)
/// where the index of the node is one. The values that have to be
/// accumulated should be given by the \c begin and \c end iterators
/// and the length of this range should be equal to the dimension
/// number of the graph.
///
///\code
/// const int DIM = 3;
/// HypercubeGraph graph(DIM);
/// dim2::Point<double> base[DIM];
/// for (int k = 0; k < DIM; ++k) {
/// base[k].x = rnd();
/// base[k].y = rnd();
/// }
/// HypercubeGraph::HyperMap<dim2::Point<double> >
/// pos(graph, base, base + DIM, dim2::Point<double>(0.0, 0.0));
///\endcode
///
/// \see HypercubeGraph
template <typename T, typename BF = std::plus<T> >
class HyperMap {
public:
/// \brief The key type of the map
typedef Node Key;
/// \brief The value type of the map
typedef T Value;
/// \brief Constructor for HyperMap.
///
/// Construct a HyperMap for the given graph. The values that have
/// to be accumulated should be given by the \c begin and \c end
/// iterators and the length of this range should be equal to the
/// dimension number of the graph.
///
/// This map accumulates the \c bf binary function with the \c fv
/// first value on that positions (dimensions) where the index of
/// the node is one.
template <typename It>
HyperMap(const Graph& graph, It begin, It end,
T fv = 0, const BF& bf = BF())
: _graph(graph), _values(begin, end), _first_value(fv), _bin_func(bf)
{
LEMON_ASSERT(_values.size() == graph.dimension(),
"Wrong size of range");
}
/// \brief The partial accumulated value.
///
/// Gives back the partial accumulated value.
Value operator[](const Key& k) const {
Value val = _first_value;
int id = _graph.index(k);
int n = 0;
while (id != 0) {
if (id & 1) {
val = _bin_func(val, _values[n]);
}
id >>= 1;
++n;
}
return val;
}
private:
const Graph& _graph;
std::vector<T> _values;
T _first_value;
BF _bin_func;
};
};
}
#endif