dust3d/thirdparty/QuadriFlow/3rd/lemon-1.3.1/lemon/static_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) 2003-2010
* 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 LEMON_STATIC_GRAPH_H
#define LEMON_STATIC_GRAPH_H
///\ingroup graphs
///\file
///\brief StaticDigraph class.
#include <lemon/core.h>
#include <lemon/bits/graph_extender.h>
namespace lemon {
class StaticDigraphBase {
public:
StaticDigraphBase()
: built(false), node_num(0), arc_num(0),
node_first_out(NULL), node_first_in(NULL),
arc_source(NULL), arc_target(NULL),
arc_next_in(NULL), arc_next_out(NULL) {}
~StaticDigraphBase() {
if (built) {
delete[] node_first_out;
delete[] node_first_in;
delete[] arc_source;
delete[] arc_target;
delete[] arc_next_out;
delete[] arc_next_in;
}
}
class Node {
friend class StaticDigraphBase;
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 Arc {
friend class StaticDigraphBase;
protected:
int id;
Arc(int _id) : id(_id) {}
public:
Arc() { }
Arc (Invalid) : id(-1) {}
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; }
};
Node source(const Arc& e) const { return Node(arc_source[e.id]); }
Node target(const Arc& e) const { return Node(arc_target[e.id]); }
void first(Node& n) const { n.id = node_num - 1; }
static void next(Node& n) { --n.id; }
void first(Arc& e) const { e.id = arc_num - 1; }
static void next(Arc& e) { --e.id; }
void firstOut(Arc& e, const Node& n) const {
e.id = node_first_out[n.id] != node_first_out[n.id + 1] ?
node_first_out[n.id] : -1;
}
void nextOut(Arc& e) const { e.id = arc_next_out[e.id]; }
void firstIn(Arc& e, const Node& n) const { e.id = node_first_in[n.id]; }
void nextIn(Arc& e) const { e.id = arc_next_in[e.id]; }
static int id(const Node& n) { return n.id; }
static Node nodeFromId(int id) { return Node(id); }
int maxNodeId() const { return node_num - 1; }
static int id(const Arc& e) { return e.id; }
static Arc arcFromId(int id) { return Arc(id); }
int maxArcId() const { return arc_num - 1; }
typedef True NodeNumTag;
typedef True ArcNumTag;
int nodeNum() const { return node_num; }
int arcNum() const { return arc_num; }
private:
template <typename Digraph, typename NodeRefMap>
class ArcLess {
public:
typedef typename Digraph::Arc Arc;
ArcLess(const Digraph &_graph, const NodeRefMap& _nodeRef)
: digraph(_graph), nodeRef(_nodeRef) {}
bool operator()(const Arc& left, const Arc& right) const {
return nodeRef[digraph.target(left)] < nodeRef[digraph.target(right)];
}
private:
const Digraph& digraph;
const NodeRefMap& nodeRef;
};
public:
typedef True BuildTag;
void clear() {
if (built) {
delete[] node_first_out;
delete[] node_first_in;
delete[] arc_source;
delete[] arc_target;
delete[] arc_next_out;
delete[] arc_next_in;
}
built = false;
node_num = 0;
arc_num = 0;
}
template <typename Digraph, typename NodeRefMap, typename ArcRefMap>
void build(const Digraph& digraph, NodeRefMap& nodeRef, ArcRefMap& arcRef) {
typedef typename Digraph::Node GNode;
typedef typename Digraph::Arc GArc;
built = true;
node_num = countNodes(digraph);
arc_num = countArcs(digraph);
node_first_out = new int[node_num + 1];
node_first_in = new int[node_num];
arc_source = new int[arc_num];
arc_target = new int[arc_num];
arc_next_out = new int[arc_num];
arc_next_in = new int[arc_num];
int node_index = 0;
for (typename Digraph::NodeIt n(digraph); n != INVALID; ++n) {
nodeRef[n] = Node(node_index);
node_first_in[node_index] = -1;
++node_index;
}
ArcLess<Digraph, NodeRefMap> arcLess(digraph, nodeRef);
int arc_index = 0;
for (typename Digraph::NodeIt n(digraph); n != INVALID; ++n) {
int source = nodeRef[n].id;
std::vector<GArc> arcs;
for (typename Digraph::OutArcIt e(digraph, n); e != INVALID; ++e) {
arcs.push_back(e);
}
if (!arcs.empty()) {
node_first_out[source] = arc_index;
std::sort(arcs.begin(), arcs.end(), arcLess);
for (typename std::vector<GArc>::iterator it = arcs.begin();
it != arcs.end(); ++it) {
int target = nodeRef[digraph.target(*it)].id;
arcRef[*it] = Arc(arc_index);
arc_source[arc_index] = source;
arc_target[arc_index] = target;
arc_next_in[arc_index] = node_first_in[target];
node_first_in[target] = arc_index;
arc_next_out[arc_index] = arc_index + 1;
++arc_index;
}
arc_next_out[arc_index - 1] = -1;
} else {
node_first_out[source] = arc_index;
}
}
node_first_out[node_num] = arc_num;
}
template <typename ArcListIterator>
void build(int n, ArcListIterator first, ArcListIterator last) {
built = true;
node_num = n;
arc_num = std::distance(first, last);
node_first_out = new int[node_num + 1];
node_first_in = new int[node_num];
arc_source = new int[arc_num];
arc_target = new int[arc_num];
arc_next_out = new int[arc_num];
arc_next_in = new int[arc_num];
for (int i = 0; i != node_num; ++i) {
node_first_in[i] = -1;
}
int arc_index = 0;
for (int i = 0; i != node_num; ++i) {
node_first_out[i] = arc_index;
for ( ; first != last && (*first).first == i; ++first) {
int j = (*first).second;
LEMON_ASSERT(j >= 0 && j < node_num,
"Wrong arc list for StaticDigraph::build()");
arc_source[arc_index] = i;
arc_target[arc_index] = j;
arc_next_in[arc_index] = node_first_in[j];
node_first_in[j] = arc_index;
arc_next_out[arc_index] = arc_index + 1;
++arc_index;
}
if (arc_index > node_first_out[i])
arc_next_out[arc_index - 1] = -1;
}
LEMON_ASSERT(first == last,
"Wrong arc list for StaticDigraph::build()");
node_first_out[node_num] = arc_num;
}
protected:
void fastFirstOut(Arc& e, const Node& n) const {
e.id = node_first_out[n.id];
}
static void fastNextOut(Arc& e) {
++e.id;
}
void fastLastOut(Arc& e, const Node& n) const {
e.id = node_first_out[n.id + 1];
}
protected:
bool built;
int node_num;
int arc_num;
int *node_first_out;
int *node_first_in;
int *arc_source;
int *arc_target;
int *arc_next_in;
int *arc_next_out;
};
typedef DigraphExtender<StaticDigraphBase> ExtendedStaticDigraphBase;
/// \ingroup graphs
///
/// \brief A static directed graph class.
///
/// \ref StaticDigraph is a highly efficient digraph implementation,
/// but it is fully static.
/// It stores only two \c int values for each node and only four \c int
/// values for each arc. Moreover it provides faster item iteration than
/// \ref ListDigraph and \ref SmartDigraph, especially using \c OutArcIt
/// iterators, since its arcs are stored in an appropriate order.
/// However it only provides build() and clear() functions and does not
/// support any other modification of the digraph.
///
/// Since this digraph structure is completely static, its nodes and arcs
/// can be indexed with integers from the ranges <tt>[0..nodeNum()-1]</tt>
/// and <tt>[0..arcNum()-1]</tt>, respectively.
/// The index of an item is the same as its ID, it can be obtained
/// using the corresponding \ref index() or \ref concepts::Digraph::id()
/// "id()" function. A node or arc with a certain index can be obtained
/// using node() or arc().
///
/// This type fully conforms to the \ref concepts::Digraph "Digraph concept".
/// Most of its member functions and nested classes are documented
/// only in the concept class.
///
/// This class provides constant time counting for nodes and arcs.
///
/// \sa concepts::Digraph
class StaticDigraph : public ExtendedStaticDigraphBase {
public:
typedef ExtendedStaticDigraphBase Parent;
public:
/// \brief Constructor
///
/// Default constructor.
StaticDigraph() : Parent() {}
/// \brief The node with the given index.
///
/// This function returns the node with the given index.
/// \sa index()
static Node node(int ix) { return Parent::nodeFromId(ix); }
/// \brief The arc with the given index.
///
/// This function returns the arc with the given index.
/// \sa index()
static Arc arc(int ix) { return Parent::arcFromId(ix); }
/// \brief The index of the given node.
///
/// This function returns the index of the the given node.
/// \sa node()
static int index(Node node) { return Parent::id(node); }
/// \brief The index of the given arc.
///
/// This function returns the index of the the given arc.
/// \sa arc()
static int index(Arc arc) { return Parent::id(arc); }
/// \brief Number of nodes.
///
/// This function returns the number of nodes.
int nodeNum() const { return node_num; }
/// \brief Number of arcs.
///
/// This function returns the number of arcs.
int arcNum() const { return arc_num; }
/// \brief Build the digraph copying another digraph.
///
/// This function builds the digraph copying another digraph of any
/// kind. It can be called more than once, but in such case, the whole
/// structure and all maps will be cleared and rebuilt.
///
/// This method also makes possible to copy a digraph to a StaticDigraph
/// structure using \ref DigraphCopy.
///
/// \param digraph An existing digraph to be copied.
/// \param nodeRef The node references will be copied into this map.
/// Its key type must be \c Digraph::Node and its value type must be
/// \c StaticDigraph::Node.
/// It must conform to the \ref concepts::ReadWriteMap "ReadWriteMap"
/// concept.
/// \param arcRef The arc references will be copied into this map.
/// Its key type must be \c Digraph::Arc and its value type must be
/// \c StaticDigraph::Arc.
/// It must conform to the \ref concepts::WriteMap "WriteMap" concept.
///
/// \note If you do not need the arc references, then you could use
/// \ref NullMap for the last parameter. However the node references
/// are required by the function itself, thus they must be readable
/// from the map.
template <typename Digraph, typename NodeRefMap, typename ArcRefMap>
void build(const Digraph& digraph, NodeRefMap& nodeRef, ArcRefMap& arcRef) {
if (built) Parent::clear();
Parent::build(digraph, nodeRef, arcRef);
}
/// \brief Build the digraph from an arc list.
///
/// This function builds the digraph from the given arc list.
/// It can be called more than once, but in such case, the whole
/// structure and all maps will be cleared and rebuilt.
///
/// The list of the arcs must be given in the range <tt>[begin, end)</tt>
/// specified by STL compatible itartors whose \c value_type must be
/// <tt>std::pair<int,int></tt>.
/// Each arc must be specified by a pair of integer indices
/// from the range <tt>[0..n-1]</tt>. <i>The pairs must be in a
/// non-decreasing order with respect to their first values.</i>
/// If the k-th pair in the list is <tt>(i,j)</tt>, then
/// <tt>arc(k-1)</tt> will connect <tt>node(i)</tt> to <tt>node(j)</tt>.
///
/// \param n The number of nodes.
/// \param begin An iterator pointing to the beginning of the arc list.
/// \param end An iterator pointing to the end of the arc list.
///
/// For example, a simple digraph can be constructed like this.
/// \code
/// std::vector<std::pair<int,int> > arcs;
/// arcs.push_back(std::make_pair(0,1));
/// arcs.push_back(std::make_pair(0,2));
/// arcs.push_back(std::make_pair(1,3));
/// arcs.push_back(std::make_pair(1,2));
/// arcs.push_back(std::make_pair(3,0));
/// StaticDigraph gr;
/// gr.build(4, arcs.begin(), arcs.end());
/// \endcode
template <typename ArcListIterator>
void build(int n, ArcListIterator begin, ArcListIterator end) {
if (built) Parent::clear();
StaticDigraphBase::build(n, begin, end);
notifier(Node()).build();
notifier(Arc()).build();
}
/// \brief Clear the digraph.
///
/// This function erases all nodes and arcs from the digraph.
void clear() {
Parent::clear();
}
protected:
using Parent::fastFirstOut;
using Parent::fastNextOut;
using Parent::fastLastOut;
public:
class OutArcIt : public Arc {
public:
OutArcIt() { }
OutArcIt(Invalid i) : Arc(i) { }
OutArcIt(const StaticDigraph& digraph, const Node& node) {
digraph.fastFirstOut(*this, node);
digraph.fastLastOut(last, node);
if (last == *this) *this = INVALID;
}
OutArcIt(const StaticDigraph& digraph, const Arc& arc) : Arc(arc) {
if (arc != INVALID) {
digraph.fastLastOut(last, digraph.source(arc));
}
}
OutArcIt& operator++() {
StaticDigraph::fastNextOut(*this);
if (last == *this) *this = INVALID;
return *this;
}
private:
Arc last;
};
Node baseNode(const OutArcIt &arc) const {
return Parent::source(static_cast<const Arc&>(arc));
}
Node runningNode(const OutArcIt &arc) const {
return Parent::target(static_cast<const Arc&>(arc));
}
Node baseNode(const InArcIt &arc) const {
return Parent::target(static_cast<const Arc&>(arc));
}
Node runningNode(const InArcIt &arc) const {
return Parent::source(static_cast<const Arc&>(arc));
}
};
}
#endif