dust3d/thirdparty/QuadriFlow/3rd/lemon-1.3.1/lemon/list_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) 2003-2013
* 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_LIST_GRAPH_H
#define LEMON_LIST_GRAPH_H
///\ingroup graphs
///\file
///\brief ListDigraph and ListGraph classes.
#include <lemon/core.h>
#include <lemon/error.h>
#include <lemon/bits/graph_extender.h>
#include <vector>
#include <list>
namespace lemon {
class ListDigraph;
class ListDigraphBase {
protected:
struct NodeT {
int first_in, first_out;
int prev, next;
};
struct ArcT {
int target, source;
int prev_in, prev_out;
int next_in, next_out;
};
std::vector<NodeT> nodes;
int first_node;
int first_free_node;
std::vector<ArcT> arcs;
int first_free_arc;
public:
typedef ListDigraphBase Digraph;
class Node {
friend class ListDigraphBase;
friend class ListDigraph;
protected:
int id;
explicit Node(int pid) { id = pid;}
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 ListDigraphBase;
friend class ListDigraph;
protected:
int id;
explicit Arc(int pid) { id = pid;}
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;}
};
ListDigraphBase()
: nodes(), first_node(-1),
first_free_node(-1), arcs(), first_free_arc(-1) {}
int maxNodeId() const { return nodes.size()-1; }
int maxArcId() const { return arcs.size()-1; }
Node source(Arc e) const { return Node(arcs[e.id].source); }
Node target(Arc e) const { return Node(arcs[e.id].target); }
void first(Node& node) const {
node.id = first_node;
}
void next(Node& node) const {
node.id = nodes[node.id].next;
}
void first(Arc& arc) const {
int n;
for(n = first_node;
n != -1 && nodes[n].first_out == -1;
n = nodes[n].next) {}
arc.id = (n == -1) ? -1 : nodes[n].first_out;
}
void next(Arc& arc) const {
if (arcs[arc.id].next_out != -1) {
arc.id = arcs[arc.id].next_out;
} else {
int n;
for(n = nodes[arcs[arc.id].source].next;
n != -1 && nodes[n].first_out == -1;
n = nodes[n].next) {}
arc.id = (n == -1) ? -1 : nodes[n].first_out;
}
}
void firstOut(Arc &e, const Node& v) const {
e.id = nodes[v.id].first_out;
}
void nextOut(Arc &e) const {
e.id=arcs[e.id].next_out;
}
void firstIn(Arc &e, const Node& v) const {
e.id = nodes[v.id].first_in;
}
void nextIn(Arc &e) const {
e.id=arcs[e.id].next_in;
}
static int id(Node v) { return v.id; }
static int id(Arc e) { return e.id; }
static Node nodeFromId(int id) { return Node(id);}
static Arc arcFromId(int id) { return Arc(id);}
bool valid(Node n) const {
return n.id >= 0 && n.id < static_cast<int>(nodes.size()) &&
nodes[n.id].prev != -2;
}
bool valid(Arc a) const {
return a.id >= 0 && a.id < static_cast<int>(arcs.size()) &&
arcs[a.id].prev_in != -2;
}
Node addNode() {
int n;
if(first_free_node==-1) {
n = nodes.size();
nodes.push_back(NodeT());
} else {
n = first_free_node;
first_free_node = nodes[n].next;
}
nodes[n].next = first_node;
if(first_node != -1) nodes[first_node].prev = n;
first_node = n;
nodes[n].prev = -1;
nodes[n].first_in = nodes[n].first_out = -1;
return Node(n);
}
Arc addArc(Node u, Node v) {
int n;
if (first_free_arc == -1) {
n = arcs.size();
arcs.push_back(ArcT());
} else {
n = first_free_arc;
first_free_arc = arcs[n].next_in;
}
arcs[n].source = u.id;
arcs[n].target = v.id;
arcs[n].next_out = nodes[u.id].first_out;
if(nodes[u.id].first_out != -1) {
arcs[nodes[u.id].first_out].prev_out = n;
}
arcs[n].next_in = nodes[v.id].first_in;
if(nodes[v.id].first_in != -1) {
arcs[nodes[v.id].first_in].prev_in = n;
}
arcs[n].prev_in = arcs[n].prev_out = -1;
nodes[u.id].first_out = nodes[v.id].first_in = n;
return Arc(n);
}
void erase(const Node& node) {
int n = node.id;
if(nodes[n].next != -1) {
nodes[nodes[n].next].prev = nodes[n].prev;
}
if(nodes[n].prev != -1) {
nodes[nodes[n].prev].next = nodes[n].next;
} else {
first_node = nodes[n].next;
}
nodes[n].next = first_free_node;
first_free_node = n;
nodes[n].prev = -2;
}
void erase(const Arc& arc) {
int n = arc.id;
if(arcs[n].next_in!=-1) {
arcs[arcs[n].next_in].prev_in = arcs[n].prev_in;
}
if(arcs[n].prev_in!=-1) {
arcs[arcs[n].prev_in].next_in = arcs[n].next_in;
} else {
nodes[arcs[n].target].first_in = arcs[n].next_in;
}
if(arcs[n].next_out!=-1) {
arcs[arcs[n].next_out].prev_out = arcs[n].prev_out;
}
if(arcs[n].prev_out!=-1) {
arcs[arcs[n].prev_out].next_out = arcs[n].next_out;
} else {
nodes[arcs[n].source].first_out = arcs[n].next_out;
}
arcs[n].next_in = first_free_arc;
first_free_arc = n;
arcs[n].prev_in = -2;
}
void clear() {
arcs.clear();
nodes.clear();
first_node = first_free_node = first_free_arc = -1;
}
protected:
void changeTarget(Arc e, Node n)
{
if(arcs[e.id].next_in != -1)
arcs[arcs[e.id].next_in].prev_in = arcs[e.id].prev_in;
if(arcs[e.id].prev_in != -1)
arcs[arcs[e.id].prev_in].next_in = arcs[e.id].next_in;
else nodes[arcs[e.id].target].first_in = arcs[e.id].next_in;
if (nodes[n.id].first_in != -1) {
arcs[nodes[n.id].first_in].prev_in = e.id;
}
arcs[e.id].target = n.id;
arcs[e.id].prev_in = -1;
arcs[e.id].next_in = nodes[n.id].first_in;
nodes[n.id].first_in = e.id;
}
void changeSource(Arc e, Node n)
{
if(arcs[e.id].next_out != -1)
arcs[arcs[e.id].next_out].prev_out = arcs[e.id].prev_out;
if(arcs[e.id].prev_out != -1)
arcs[arcs[e.id].prev_out].next_out = arcs[e.id].next_out;
else nodes[arcs[e.id].source].first_out = arcs[e.id].next_out;
if (nodes[n.id].first_out != -1) {
arcs[nodes[n.id].first_out].prev_out = e.id;
}
arcs[e.id].source = n.id;
arcs[e.id].prev_out = -1;
arcs[e.id].next_out = nodes[n.id].first_out;
nodes[n.id].first_out = e.id;
}
};
typedef DigraphExtender<ListDigraphBase> ExtendedListDigraphBase;
/// \addtogroup graphs
/// @{
///A general directed graph structure.
///\ref ListDigraph is a versatile and fast directed graph
///implementation based on linked lists that are stored in
///\c std::vector structures.
///
///This type fully conforms to the \ref concepts::Digraph "Digraph concept"
///and it also provides several useful additional functionalities.
///Most of its member functions and nested classes are documented
///only in the concept class.
///
///This class provides only linear time counting for nodes and arcs.
///
///\sa concepts::Digraph
///\sa ListGraph
class ListDigraph : public ExtendedListDigraphBase {
typedef ExtendedListDigraphBase Parent;
private:
/// Digraphs are \e not copy constructible. Use DigraphCopy instead.
ListDigraph(const ListDigraph &) :ExtendedListDigraphBase() {};
/// \brief Assignment of a digraph to another one is \e not allowed.
/// Use DigraphCopy instead.
void operator=(const ListDigraph &) {}
public:
/// Constructor
/// Constructor.
///
ListDigraph() {}
///Add a new node to the digraph.
///This function adds a new node to the digraph.
///\return The new node.
Node addNode() { return Parent::addNode(); }
///Add a new arc to the digraph.
///This function adds a new arc to the digraph with source node \c s
///and target node \c t.
///\return The new arc.
Arc addArc(Node s, Node t) {
return Parent::addArc(s, t);
}
///\brief Erase a node from the digraph.
///
///This function erases the given node along with its outgoing and
///incoming arcs from the digraph.
///
///\note All iterators referencing the removed node or the connected
///arcs are invalidated, of course.
void erase(Node n) { Parent::erase(n); }
///\brief Erase an arc from the digraph.
///
///This function erases the given arc from the digraph.
///
///\note All iterators referencing the removed arc are invalidated,
///of course.
void erase(Arc a) { Parent::erase(a); }
/// Node validity check
/// This function gives back \c true if the given node is valid,
/// i.e. it is a real node of the digraph.
///
/// \warning A removed node could become valid again if new nodes are
/// added to the digraph.
bool valid(Node n) const { return Parent::valid(n); }
/// Arc validity check
/// This function gives back \c true if the given arc is valid,
/// i.e. it is a real arc of the digraph.
///
/// \warning A removed arc could become valid again if new arcs are
/// added to the digraph.
bool valid(Arc a) const { return Parent::valid(a); }
/// Change the target node of an arc
/// This function changes the target node of the given arc \c a to \c n.
///
///\note \c ArcIt and \c OutArcIt iterators referencing the changed
///arc remain valid, but \c InArcIt iterators are invalidated.
///
///\warning This functionality cannot be used together with the Snapshot
///feature.
void changeTarget(Arc a, Node n) {
Parent::changeTarget(a,n);
}
/// Change the source node of an arc
/// This function changes the source node of the given arc \c a to \c n.
///
///\note \c InArcIt iterators referencing the changed arc remain
///valid, but \c ArcIt and \c OutArcIt iterators are invalidated.
///
///\warning This functionality cannot be used together with the Snapshot
///feature.
void changeSource(Arc a, Node n) {
Parent::changeSource(a,n);
}
/// Reverse the direction of an arc.
/// This function reverses the direction of the given arc.
///\note \c ArcIt, \c OutArcIt and \c InArcIt iterators referencing
///the changed arc are invalidated.
///
///\warning This functionality cannot be used together with the Snapshot
///feature.
void reverseArc(Arc a) {
Node t=target(a);
changeTarget(a,source(a));
changeSource(a,t);
}
///Contract two nodes.
///This function contracts the given two nodes.
///Node \c v is removed, but instead of deleting its
///incident arcs, they are joined to node \c u.
///If the last parameter \c r is \c true (this is the default value),
///then the newly created loops are removed.
///
///\note The moved arcs are joined to node \c u using changeSource()
///or changeTarget(), thus \c ArcIt and \c OutArcIt iterators are
///invalidated for the outgoing arcs of node \c v and \c InArcIt
///iterators are invalidated for the incoming arcs of \c v.
///Moreover all iterators referencing node \c v or the removed
///loops are also invalidated. Other iterators remain valid.
///
///\warning This functionality cannot be used together with the Snapshot
///feature.
void contract(Node u, Node v, bool r = true)
{
for(OutArcIt e(*this,v);e!=INVALID;) {
OutArcIt f=e;
++f;
if(r && target(e)==u) erase(e);
else changeSource(e,u);
e=f;
}
for(InArcIt e(*this,v);e!=INVALID;) {
InArcIt f=e;
++f;
if(r && source(e)==u) erase(e);
else changeTarget(e,u);
e=f;
}
erase(v);
}
///Split a node.
///This function splits the given node. First, a new node is added
///to the digraph, then the source of each outgoing arc of node \c n
///is moved to this new node.
///If the second parameter \c connect is \c true (this is the default
///value), then a new arc from node \c n to the newly created node
///is also added.
///\return The newly created node.
///
///\note All iterators remain valid.
///
///\warning This functionality cannot be used together with the
///Snapshot feature.
Node split(Node n, bool connect = true) {
Node b = addNode();
nodes[b.id].first_out=nodes[n.id].first_out;
nodes[n.id].first_out=-1;
for(int i=nodes[b.id].first_out; i!=-1; i=arcs[i].next_out) {
arcs[i].source=b.id;
}
if (connect) addArc(n,b);
return b;
}
///Split an arc.
///This function splits the given arc. First, a new node \c v is
///added to the digraph, then the target node of the original arc
///is set to \c v. Finally, an arc from \c v to the original target
///is added.
///\return The newly created node.
///
///\note \c InArcIt iterators referencing the original arc are
///invalidated. Other iterators remain valid.
///
///\warning This functionality cannot be used together with the
///Snapshot feature.
Node split(Arc a) {
Node v = addNode();
addArc(v,target(a));
changeTarget(a,v);
return v;
}
///Clear the digraph.
///This function erases all nodes and arcs from the digraph.
///
///\note All iterators of the digraph are invalidated, of course.
void clear() {
Parent::clear();
}
/// Reserve memory for nodes.
/// Using this function, it is possible to avoid superfluous memory
/// allocation: if you know that the digraph you want to build will
/// be large (e.g. it will contain millions of nodes and/or arcs),
/// then it is worth reserving space for this amount before starting
/// to build the digraph.
/// \sa reserveArc()
void reserveNode(int n) { nodes.reserve(n); };
/// Reserve memory for arcs.
/// Using this function, it is possible to avoid superfluous memory
/// allocation: if you know that the digraph you want to build will
/// be large (e.g. it will contain millions of nodes and/or arcs),
/// then it is worth reserving space for this amount before starting
/// to build the digraph.
/// \sa reserveNode()
void reserveArc(int m) { arcs.reserve(m); };
/// \brief Class to make a snapshot of the digraph and restore
/// it later.
///
/// Class to make a snapshot of the digraph and restore it later.
///
/// The newly added nodes and arcs can be removed using the
/// restore() function.
///
/// \note After a state is restored, you cannot restore a later state,
/// i.e. you cannot add the removed nodes and arcs again using
/// another Snapshot instance.
///
/// \warning Node and arc deletions and other modifications (e.g.
/// reversing, contracting, splitting arcs or nodes) cannot be
/// restored. These events invalidate the snapshot.
/// However, the arcs and nodes that were added to the digraph after
/// making the current snapshot can be removed without invalidating it.
class Snapshot {
protected:
typedef Parent::NodeNotifier NodeNotifier;
class NodeObserverProxy : public NodeNotifier::ObserverBase {
public:
NodeObserverProxy(Snapshot& _snapshot)
: snapshot(_snapshot) {}
using NodeNotifier::ObserverBase::attach;
using NodeNotifier::ObserverBase::detach;
using NodeNotifier::ObserverBase::attached;
protected:
virtual void add(const Node& node) {
snapshot.addNode(node);
}
virtual void add(const std::vector<Node>& nodes) {
for (int i = nodes.size() - 1; i >= 0; ++i) {
snapshot.addNode(nodes[i]);
}
}
virtual void erase(const Node& node) {
snapshot.eraseNode(node);
}
virtual void erase(const std::vector<Node>& nodes) {
for (int i = 0; i < int(nodes.size()); ++i) {
snapshot.eraseNode(nodes[i]);
}
}
virtual void build() {
Node node;
std::vector<Node> nodes;
for (notifier()->first(node); node != INVALID;
notifier()->next(node)) {
nodes.push_back(node);
}
for (int i = nodes.size() - 1; i >= 0; --i) {
snapshot.addNode(nodes[i]);
}
}
virtual void clear() {
Node node;
for (notifier()->first(node); node != INVALID;
notifier()->next(node)) {
snapshot.eraseNode(node);
}
}
Snapshot& snapshot;
};
class ArcObserverProxy : public ArcNotifier::ObserverBase {
public:
ArcObserverProxy(Snapshot& _snapshot)
: snapshot(_snapshot) {}
using ArcNotifier::ObserverBase::attach;
using ArcNotifier::ObserverBase::detach;
using ArcNotifier::ObserverBase::attached;
protected:
virtual void add(const Arc& arc) {
snapshot.addArc(arc);
}
virtual void add(const std::vector<Arc>& arcs) {
for (int i = arcs.size() - 1; i >= 0; ++i) {
snapshot.addArc(arcs[i]);
}
}
virtual void erase(const Arc& arc) {
snapshot.eraseArc(arc);
}
virtual void erase(const std::vector<Arc>& arcs) {
for (int i = 0; i < int(arcs.size()); ++i) {
snapshot.eraseArc(arcs[i]);
}
}
virtual void build() {
Arc arc;
std::vector<Arc> arcs;
for (notifier()->first(arc); arc != INVALID;
notifier()->next(arc)) {
arcs.push_back(arc);
}
for (int i = arcs.size() - 1; i >= 0; --i) {
snapshot.addArc(arcs[i]);
}
}
virtual void clear() {
Arc arc;
for (notifier()->first(arc); arc != INVALID;
notifier()->next(arc)) {
snapshot.eraseArc(arc);
}
}
Snapshot& snapshot;
};
ListDigraph *digraph;
NodeObserverProxy node_observer_proxy;
ArcObserverProxy arc_observer_proxy;
std::list<Node> added_nodes;
std::list<Arc> added_arcs;
void addNode(const Node& node) {
added_nodes.push_front(node);
}
void eraseNode(const Node& node) {
std::list<Node>::iterator it =
std::find(added_nodes.begin(), added_nodes.end(), node);
if (it == added_nodes.end()) {
clear();
arc_observer_proxy.detach();
throw NodeNotifier::ImmediateDetach();
} else {
added_nodes.erase(it);
}
}
void addArc(const Arc& arc) {
added_arcs.push_front(arc);
}
void eraseArc(const Arc& arc) {
std::list<Arc>::iterator it =
std::find(added_arcs.begin(), added_arcs.end(), arc);
if (it == added_arcs.end()) {
clear();
node_observer_proxy.detach();
throw ArcNotifier::ImmediateDetach();
} else {
added_arcs.erase(it);
}
}
void attach(ListDigraph &_digraph) {
digraph = &_digraph;
node_observer_proxy.attach(digraph->notifier(Node()));
arc_observer_proxy.attach(digraph->notifier(Arc()));
}
void detach() {
node_observer_proxy.detach();
arc_observer_proxy.detach();
}
bool attached() const {
return node_observer_proxy.attached();
}
void clear() {
added_nodes.clear();
added_arcs.clear();
}
public:
/// \brief Default constructor.
///
/// Default constructor.
/// You have to call save() to actually make a snapshot.
Snapshot()
: digraph(0), node_observer_proxy(*this),
arc_observer_proxy(*this) {}
/// \brief Constructor that immediately makes a snapshot.
///
/// This constructor immediately makes a snapshot of the given digraph.
Snapshot(ListDigraph &gr)
: node_observer_proxy(*this),
arc_observer_proxy(*this) {
attach(gr);
}
/// \brief Make a snapshot.
///
/// This function makes a snapshot of the given digraph.
/// It can be called more than once. In case of a repeated
/// call, the previous snapshot gets lost.
void save(ListDigraph &gr) {
if (attached()) {
detach();
clear();
}
attach(gr);
}
/// \brief Undo the changes until the last snapshot.
///
/// This function undos the changes until the last snapshot
/// created by save() or Snapshot(ListDigraph&).
///
/// \warning This method invalidates the snapshot, i.e. repeated
/// restoring is not supported unless you call save() again.
void restore() {
detach();
for(std::list<Arc>::iterator it = added_arcs.begin();
it != added_arcs.end(); ++it) {
digraph->erase(*it);
}
for(std::list<Node>::iterator it = added_nodes.begin();
it != added_nodes.end(); ++it) {
digraph->erase(*it);
}
clear();
}
/// \brief Returns \c true if the snapshot is valid.
///
/// This function returns \c true if the snapshot is valid.
bool valid() const {
return attached();
}
};
};
///@}
class ListGraphBase {
protected:
struct NodeT {
int first_out;
int prev, next;
};
struct ArcT {
int target;
int prev_out, next_out;
};
std::vector<NodeT> nodes;
int first_node;
int first_free_node;
std::vector<ArcT> arcs;
int first_free_arc;
public:
typedef ListGraphBase Graph;
class Node {
friend class ListGraphBase;
protected:
int id;
explicit Node(int pid) { id = pid;}
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 ListGraphBase;
protected:
int id;
explicit Edge(int pid) { id = pid;}
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 ListGraphBase;
protected:
int id;
explicit Arc(int pid) { id = pid;}
public:
operator Edge() const {
return id != -1 ? edgeFromId(id / 2) : INVALID;
}
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;}
};
ListGraphBase()
: nodes(), first_node(-1),
first_free_node(-1), arcs(), first_free_arc(-1) {}
int maxNodeId() const { return nodes.size()-1; }
int maxEdgeId() const { return arcs.size() / 2 - 1; }
int maxArcId() const { return arcs.size()-1; }
Node source(Arc e) const { return Node(arcs[e.id ^ 1].target); }
Node target(Arc e) const { return Node(arcs[e.id].target); }
Node u(Edge e) const { return Node(arcs[2 * e.id].target); }
Node v(Edge e) const { return Node(arcs[2 * e.id + 1].target); }
static bool direction(Arc e) {
return (e.id & 1) == 1;
}
static Arc direct(Edge e, bool d) {
return Arc(e.id * 2 + (d ? 1 : 0));
}
void first(Node& node) const {
node.id = first_node;
}
void next(Node& node) const {
node.id = nodes[node.id].next;
}
void first(Arc& e) const {
int n = first_node;
while (n != -1 && nodes[n].first_out == -1) {
n = nodes[n].next;
}
e.id = (n == -1) ? -1 : nodes[n].first_out;
}
void next(Arc& e) const {
if (arcs[e.id].next_out != -1) {
e.id = arcs[e.id].next_out;
} else {
int n = nodes[arcs[e.id ^ 1].target].next;
while(n != -1 && nodes[n].first_out == -1) {
n = nodes[n].next;
}
e.id = (n == -1) ? -1 : nodes[n].first_out;
}
}
void first(Edge& e) const {
int n = first_node;
while (n != -1) {
e.id = nodes[n].first_out;
while ((e.id & 1) != 1) {
e.id = arcs[e.id].next_out;
}
if (e.id != -1) {
e.id /= 2;
return;
}
n = nodes[n].next;
}
e.id = -1;
}
void next(Edge& e) const {
int n = arcs[e.id * 2].target;
e.id = arcs[(e.id * 2) | 1].next_out;
while ((e.id & 1) != 1) {
e.id = arcs[e.id].next_out;
}
if (e.id != -1) {
e.id /= 2;
return;
}
n = nodes[n].next;
while (n != -1) {
e.id = nodes[n].first_out;
while ((e.id & 1) != 1) {
e.id = arcs[e.id].next_out;
}
if (e.id != -1) {
e.id /= 2;
return;
}
n = nodes[n].next;
}
e.id = -1;
}
void firstOut(Arc &e, const Node& v) const {
e.id = nodes[v.id].first_out;
}
void nextOut(Arc &e) const {
e.id = arcs[e.id].next_out;
}
void firstIn(Arc &e, const Node& v) const {
e.id = ((nodes[v.id].first_out) ^ 1);
if (e.id == -2) e.id = -1;
}
void nextIn(Arc &e) const {
e.id = ((arcs[e.id ^ 1].next_out) ^ 1);
if (e.id == -2) e.id = -1;
}
void firstInc(Edge &e, bool& d, const Node& v) const {
int a = nodes[v.id].first_out;
if (a != -1 ) {
e.id = a / 2;
d = ((a & 1) == 1);
} else {
e.id = -1;
d = true;
}
}
void nextInc(Edge &e, bool& d) const {
int a = (arcs[(e.id * 2) | (d ? 1 : 0)].next_out);
if (a != -1 ) {
e.id = a / 2;
d = ((a & 1) == 1);
} else {
e.id = -1;
d = true;
}
}
static int id(Node v) { return v.id; }
static int id(Arc e) { return e.id; }
static int id(Edge e) { return e.id; }
static Node nodeFromId(int id) { return Node(id);}
static Arc arcFromId(int id) { return Arc(id);}
static Edge edgeFromId(int id) { return Edge(id);}
bool valid(Node n) const {
return n.id >= 0 && n.id < static_cast<int>(nodes.size()) &&
nodes[n.id].prev != -2;
}
bool valid(Arc a) const {
return a.id >= 0 && a.id < static_cast<int>(arcs.size()) &&
arcs[a.id].prev_out != -2;
}
bool valid(Edge e) const {
return e.id >= 0 && 2 * e.id < static_cast<int>(arcs.size()) &&
arcs[2 * e.id].prev_out != -2;
}
Node addNode() {
int n;
if(first_free_node==-1) {
n = nodes.size();
nodes.push_back(NodeT());
} else {
n = first_free_node;
first_free_node = nodes[n].next;
}
nodes[n].next = first_node;
if (first_node != -1) nodes[first_node].prev = n;
first_node = n;
nodes[n].prev = -1;
nodes[n].first_out = -1;
return Node(n);
}
Edge addEdge(Node u, Node v) {
int n;
if (first_free_arc == -1) {
n = arcs.size();
arcs.push_back(ArcT());
arcs.push_back(ArcT());
} else {
n = first_free_arc;
first_free_arc = arcs[n].next_out;
}
arcs[n].target = u.id;
arcs[n | 1].target = v.id;
arcs[n].next_out = nodes[v.id].first_out;
if (nodes[v.id].first_out != -1) {
arcs[nodes[v.id].first_out].prev_out = n;
}
arcs[n].prev_out = -1;
nodes[v.id].first_out = n;
arcs[n | 1].next_out = nodes[u.id].first_out;
if (nodes[u.id].first_out != -1) {
arcs[nodes[u.id].first_out].prev_out = (n | 1);
}
arcs[n | 1].prev_out = -1;
nodes[u.id].first_out = (n | 1);
return Edge(n / 2);
}
void erase(const Node& node) {
int n = node.id;
if(nodes[n].next != -1) {
nodes[nodes[n].next].prev = nodes[n].prev;
}
if(nodes[n].prev != -1) {
nodes[nodes[n].prev].next = nodes[n].next;
} else {
first_node = nodes[n].next;
}
nodes[n].next = first_free_node;
first_free_node = n;
nodes[n].prev = -2;
}
void erase(const Edge& edge) {
int n = edge.id * 2;
if (arcs[n].next_out != -1) {
arcs[arcs[n].next_out].prev_out = arcs[n].prev_out;
}
if (arcs[n].prev_out != -1) {
arcs[arcs[n].prev_out].next_out = arcs[n].next_out;
} else {
nodes[arcs[n | 1].target].first_out = arcs[n].next_out;
}
if (arcs[n | 1].next_out != -1) {
arcs[arcs[n | 1].next_out].prev_out = arcs[n | 1].prev_out;
}
if (arcs[n | 1].prev_out != -1) {
arcs[arcs[n | 1].prev_out].next_out = arcs[n | 1].next_out;
} else {
nodes[arcs[n].target].first_out = arcs[n | 1].next_out;
}
arcs[n].next_out = first_free_arc;
first_free_arc = n;
arcs[n].prev_out = -2;
arcs[n | 1].prev_out = -2;
}
void clear() {
arcs.clear();
nodes.clear();
first_node = first_free_node = first_free_arc = -1;
}
protected:
void changeV(Edge e, Node n) {
if(arcs[2 * e.id].next_out != -1) {
arcs[arcs[2 * e.id].next_out].prev_out = arcs[2 * e.id].prev_out;
}
if(arcs[2 * e.id].prev_out != -1) {
arcs[arcs[2 * e.id].prev_out].next_out =
arcs[2 * e.id].next_out;
} else {
nodes[arcs[(2 * e.id) | 1].target].first_out =
arcs[2 * e.id].next_out;
}
if (nodes[n.id].first_out != -1) {
arcs[nodes[n.id].first_out].prev_out = 2 * e.id;
}
arcs[(2 * e.id) | 1].target = n.id;
arcs[2 * e.id].prev_out = -1;
arcs[2 * e.id].next_out = nodes[n.id].first_out;
nodes[n.id].first_out = 2 * e.id;
}
void changeU(Edge e, Node n) {
if(arcs[(2 * e.id) | 1].next_out != -1) {
arcs[arcs[(2 * e.id) | 1].next_out].prev_out =
arcs[(2 * e.id) | 1].prev_out;
}
if(arcs[(2 * e.id) | 1].prev_out != -1) {
arcs[arcs[(2 * e.id) | 1].prev_out].next_out =
arcs[(2 * e.id) | 1].next_out;
} else {
nodes[arcs[2 * e.id].target].first_out =
arcs[(2 * e.id) | 1].next_out;
}
if (nodes[n.id].first_out != -1) {
arcs[nodes[n.id].first_out].prev_out = ((2 * e.id) | 1);
}
arcs[2 * e.id].target = n.id;
arcs[(2 * e.id) | 1].prev_out = -1;
arcs[(2 * e.id) | 1].next_out = nodes[n.id].first_out;
nodes[n.id].first_out = ((2 * e.id) | 1);
}
};
typedef GraphExtender<ListGraphBase> ExtendedListGraphBase;
/// \addtogroup graphs
/// @{
///A general undirected graph structure.
///\ref ListGraph is a versatile and fast undirected graph
///implementation based on linked lists that are stored in
///\c std::vector structures.
///
///This type fully conforms to the \ref concepts::Graph "Graph concept"
///and it also provides several useful additional functionalities.
///Most of its member functions and nested classes are documented
///only in the concept class.
///
///This class provides only linear time counting for nodes, edges and arcs.
///
///\sa concepts::Graph
///\sa ListDigraph
class ListGraph : public ExtendedListGraphBase {
typedef ExtendedListGraphBase Parent;
private:
/// Graphs are \e not copy constructible. Use GraphCopy instead.
ListGraph(const ListGraph &) :ExtendedListGraphBase() {};
/// \brief Assignment of a graph to another one is \e not allowed.
/// Use GraphCopy instead.
void operator=(const ListGraph &) {}
public:
/// Constructor
/// Constructor.
///
ListGraph() {}
typedef Parent::OutArcIt IncEdgeIt;
/// \brief Add a new node to the graph.
///
/// This function adds a new node to the graph.
/// \return The new node.
Node addNode() { return Parent::addNode(); }
/// \brief Add a new edge to the graph.
///
/// This function adds a new edge to the graph between nodes
/// \c u and \c v with inherent orientation from node \c u to
/// node \c v.
/// \return The new edge.
Edge addEdge(Node u, Node v) {
return Parent::addEdge(u, v);
}
///\brief Erase a node from the graph.
///
/// This function erases the given node along with its incident arcs
/// from the graph.
///
/// \note All iterators referencing the removed node or the incident
/// edges are invalidated, of course.
void erase(Node n) { Parent::erase(n); }
///\brief Erase an edge from the graph.
///
/// This function erases the given edge from the graph.
///
/// \note All iterators referencing the removed edge are invalidated,
/// of course.
void erase(Edge e) { Parent::erase(e); }
/// Node validity check
/// This function gives back \c true if the given node is valid,
/// i.e. it is a real node of the graph.
///
/// \warning A removed node could become valid again if new nodes are
/// added to the graph.
bool valid(Node n) const { return Parent::valid(n); }
/// Edge validity check
/// This function gives back \c true if the given edge is valid,
/// i.e. it is a real edge of the graph.
///
/// \warning A removed edge could become valid again if new edges are
/// added to the graph.
bool valid(Edge e) const { return Parent::valid(e); }
/// Arc validity check
/// This function gives back \c true if the given arc is valid,
/// i.e. it is a real arc of the graph.
///
/// \warning A removed arc could become valid again if new edges are
/// added to the graph.
bool valid(Arc a) const { return Parent::valid(a); }
/// \brief Change the first node of an edge.
///
/// This function changes the first node of the given edge \c e to \c n.
///
///\note \c EdgeIt and \c ArcIt iterators referencing the
///changed edge are invalidated and all other iterators whose
///base node is the changed node are also invalidated.
///
///\warning This functionality cannot be used together with the
///Snapshot feature.
void changeU(Edge e, Node n) {
Parent::changeU(e,n);
}
/// \brief Change the second node of an edge.
///
/// This function changes the second node of the given edge \c e to \c n.
///
///\note \c EdgeIt iterators referencing the changed edge remain
///valid, but \c ArcIt iterators referencing the changed edge and
///all other iterators whose base node is the changed node are also
///invalidated.
///
///\warning This functionality cannot be used together with the
///Snapshot feature.
void changeV(Edge e, Node n) {
Parent::changeV(e,n);
}
/// \brief Contract two nodes.
///
/// This function contracts the given two nodes.
/// Node \c b is removed, but instead of deleting
/// its incident edges, they are joined to node \c a.
/// If the last parameter \c r is \c true (this is the default value),
/// then the newly created loops are removed.
///
/// \note The moved edges are joined to node \c a using changeU()
/// or changeV(), thus all edge and arc iterators whose base node is
/// \c b are invalidated.
/// Moreover all iterators referencing node \c b or the removed
/// loops are also invalidated. Other iterators remain valid.
///
///\warning This functionality cannot be used together with the
///Snapshot feature.
void contract(Node a, Node b, bool r = true) {
for(IncEdgeIt e(*this, b); e!=INVALID;) {
IncEdgeIt f = e; ++f;
if (r && runningNode(e) == a) {
erase(e);
} else if (u(e) == b) {
changeU(e, a);
} else {
changeV(e, a);
}
e = f;
}
erase(b);
}
///Clear the graph.
///This function erases all nodes and arcs from the graph.
///
///\note All iterators of the graph are invalidated, of course.
void clear() {
Parent::clear();
}
/// Reserve memory for nodes.
/// Using this function, it is possible to avoid superfluous memory
/// allocation: if you know that the graph you want to build will
/// be large (e.g. it will contain millions of nodes and/or edges),
/// then it is worth reserving space for this amount before starting
/// to build the graph.
/// \sa reserveEdge()
void reserveNode(int n) { nodes.reserve(n); };
/// Reserve memory for edges.
/// Using this function, it is possible to avoid superfluous memory
/// allocation: if you know that the graph you want to build will
/// be large (e.g. it will contain millions of nodes and/or edges),
/// then it is worth reserving space for this amount before starting
/// to build the graph.
/// \sa reserveNode()
void reserveEdge(int m) { arcs.reserve(2 * m); };
/// \brief Class to make a snapshot of the graph and restore
/// it later.
///
/// Class to make a snapshot of the graph and restore it later.
///
/// The newly added nodes and edges can be removed
/// using the restore() function.
///
/// \note After a state is restored, you cannot restore a later state,
/// i.e. you cannot add the removed nodes and edges again using
/// another Snapshot instance.
///
/// \warning Node and edge deletions and other modifications
/// (e.g. changing the end-nodes of edges or contracting nodes)
/// cannot be restored. These events invalidate the snapshot.
/// However, the edges and nodes that were added to the graph after
/// making the current snapshot can be removed without invalidating it.
class Snapshot {
protected:
typedef Parent::NodeNotifier NodeNotifier;
class NodeObserverProxy : public NodeNotifier::ObserverBase {
public:
NodeObserverProxy(Snapshot& _snapshot)
: snapshot(_snapshot) {}
using NodeNotifier::ObserverBase::attach;
using NodeNotifier::ObserverBase::detach;
using NodeNotifier::ObserverBase::attached;
protected:
virtual void add(const Node& node) {
snapshot.addNode(node);
}
virtual void add(const std::vector<Node>& nodes) {
for (int i = nodes.size() - 1; i >= 0; ++i) {
snapshot.addNode(nodes[i]);
}
}
virtual void erase(const Node& node) {
snapshot.eraseNode(node);
}
virtual void erase(const std::vector<Node>& nodes) {
for (int i = 0; i < int(nodes.size()); ++i) {
snapshot.eraseNode(nodes[i]);
}
}
virtual void build() {
Node node;
std::vector<Node> nodes;
for (notifier()->first(node); node != INVALID;
notifier()->next(node)) {
nodes.push_back(node);
}
for (int i = nodes.size() - 1; i >= 0; --i) {
snapshot.addNode(nodes[i]);
}
}
virtual void clear() {
Node node;
for (notifier()->first(node); node != INVALID;
notifier()->next(node)) {
snapshot.eraseNode(node);
}
}
Snapshot& snapshot;
};
class EdgeObserverProxy : public EdgeNotifier::ObserverBase {
public:
EdgeObserverProxy(Snapshot& _snapshot)
: snapshot(_snapshot) {}
using EdgeNotifier::ObserverBase::attach;
using EdgeNotifier::ObserverBase::detach;
using EdgeNotifier::ObserverBase::attached;
protected:
virtual void add(const Edge& edge) {
snapshot.addEdge(edge);
}
virtual void add(const std::vector<Edge>& edges) {
for (int i = edges.size() - 1; i >= 0; ++i) {
snapshot.addEdge(edges[i]);
}
}
virtual void erase(const Edge& edge) {
snapshot.eraseEdge(edge);
}
virtual void erase(const std::vector<Edge>& edges) {
for (int i = 0; i < int(edges.size()); ++i) {
snapshot.eraseEdge(edges[i]);
}
}
virtual void build() {
Edge edge;
std::vector<Edge> edges;
for (notifier()->first(edge); edge != INVALID;
notifier()->next(edge)) {
edges.push_back(edge);
}
for (int i = edges.size() - 1; i >= 0; --i) {
snapshot.addEdge(edges[i]);
}
}
virtual void clear() {
Edge edge;
for (notifier()->first(edge); edge != INVALID;
notifier()->next(edge)) {
snapshot.eraseEdge(edge);
}
}
Snapshot& snapshot;
};
ListGraph *graph;
NodeObserverProxy node_observer_proxy;
EdgeObserverProxy edge_observer_proxy;
std::list<Node> added_nodes;
std::list<Edge> added_edges;
void addNode(const Node& node) {
added_nodes.push_front(node);
}
void eraseNode(const Node& node) {
std::list<Node>::iterator it =
std::find(added_nodes.begin(), added_nodes.end(), node);
if (it == added_nodes.end()) {
clear();
edge_observer_proxy.detach();
throw NodeNotifier::ImmediateDetach();
} else {
added_nodes.erase(it);
}
}
void addEdge(const Edge& edge) {
added_edges.push_front(edge);
}
void eraseEdge(const Edge& edge) {
std::list<Edge>::iterator it =
std::find(added_edges.begin(), added_edges.end(), edge);
if (it == added_edges.end()) {
clear();
node_observer_proxy.detach();
throw EdgeNotifier::ImmediateDetach();
} else {
added_edges.erase(it);
}
}
void attach(ListGraph &_graph) {
graph = &_graph;
node_observer_proxy.attach(graph->notifier(Node()));
edge_observer_proxy.attach(graph->notifier(Edge()));
}
void detach() {
node_observer_proxy.detach();
edge_observer_proxy.detach();
}
bool attached() const {
return node_observer_proxy.attached();
}
void clear() {
added_nodes.clear();
added_edges.clear();
}
public:
/// \brief Default constructor.
///
/// Default constructor.
/// You have to call save() to actually make a snapshot.
Snapshot()
: graph(0), node_observer_proxy(*this),
edge_observer_proxy(*this) {}
/// \brief Constructor that immediately makes a snapshot.
///
/// This constructor immediately makes a snapshot of the given graph.
Snapshot(ListGraph &gr)
: node_observer_proxy(*this),
edge_observer_proxy(*this) {
attach(gr);
}
/// \brief Make a snapshot.
///
/// This function makes a snapshot of the given graph.
/// It can be called more than once. In case of a repeated
/// call, the previous snapshot gets lost.
void save(ListGraph &gr) {
if (attached()) {
detach();
clear();
}
attach(gr);
}
/// \brief Undo the changes until the last snapshot.
///
/// This function undos the changes until the last snapshot
/// created by save() or Snapshot(ListGraph&).
///
/// \warning This method invalidates the snapshot, i.e. repeated
/// restoring is not supported unless you call save() again.
void restore() {
detach();
for(std::list<Edge>::iterator it = added_edges.begin();
it != added_edges.end(); ++it) {
graph->erase(*it);
}
for(std::list<Node>::iterator it = added_nodes.begin();
it != added_nodes.end(); ++it) {
graph->erase(*it);
}
clear();
}
/// \brief Returns \c true if the snapshot is valid.
///
/// This function returns \c true if the snapshot is valid.
bool valid() const {
return attached();
}
};
};
/// @}
class ListBpGraphBase {
protected:
struct NodeT {
int first_out;
int prev, next;
int partition_prev, partition_next;
int partition_index;
bool red;
};
struct ArcT {
int target;
int prev_out, next_out;
};
std::vector<NodeT> nodes;
int first_node, first_red, first_blue;
int max_red, max_blue;
int first_free_red, first_free_blue;
std::vector<ArcT> arcs;
int first_free_arc;
public:
typedef ListBpGraphBase BpGraph;
class Node {
friend class ListBpGraphBase;
protected:
int id;
explicit Node(int pid) { id = pid;}
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 RedNode : public Node {
friend class ListBpGraphBase;
protected:
explicit RedNode(int pid) : Node(pid) {}
public:
RedNode() {}
RedNode(const RedNode& node) : Node(node) {}
RedNode(Invalid) : Node(INVALID){}
};
class BlueNode : public Node {
friend class ListBpGraphBase;
protected:
explicit BlueNode(int pid) : Node(pid) {}
public:
BlueNode() {}
BlueNode(const BlueNode& node) : Node(node) {}
BlueNode(Invalid) : Node(INVALID){}
};
class Edge {
friend class ListBpGraphBase;
protected:
int id;
explicit Edge(int pid) { id = pid;}
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 ListBpGraphBase;
protected:
int id;
explicit Arc(int pid) { id = pid;}
public:
operator Edge() const {
return id != -1 ? edgeFromId(id / 2) : INVALID;
}
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;}
};
ListBpGraphBase()
: nodes(), first_node(-1),
first_red(-1), first_blue(-1),
max_red(-1), max_blue(-1),
first_free_red(-1), first_free_blue(-1),
arcs(), first_free_arc(-1) {}
bool red(Node n) const { return nodes[n.id].red; }
bool blue(Node n) const { return !nodes[n.id].red; }
static RedNode asRedNodeUnsafe(Node n) { return RedNode(n.id); }
static BlueNode asBlueNodeUnsafe(Node n) { return BlueNode(n.id); }
int maxNodeId() const { return nodes.size()-1; }
int maxRedId() const { return max_red; }
int maxBlueId() const { return max_blue; }
int maxEdgeId() const { return arcs.size() / 2 - 1; }
int maxArcId() const { return arcs.size()-1; }
Node source(Arc e) const { return Node(arcs[e.id ^ 1].target); }
Node target(Arc e) const { return Node(arcs[e.id].target); }
RedNode redNode(Edge e) const {
return RedNode(arcs[2 * e.id].target);
}
BlueNode blueNode(Edge e) const {
return BlueNode(arcs[2 * e.id + 1].target);
}
static bool direction(Arc e) {
return (e.id & 1) == 1;
}
static Arc direct(Edge e, bool d) {
return Arc(e.id * 2 + (d ? 1 : 0));
}
void first(Node& node) const {
node.id = first_node;
}
void next(Node& node) const {
node.id = nodes[node.id].next;
}
void first(RedNode& node) const {
node.id = first_red;
}
void next(RedNode& node) const {
node.id = nodes[node.id].partition_next;
}
void first(BlueNode& node) const {
node.id = first_blue;
}
void next(BlueNode& node) const {
node.id = nodes[node.id].partition_next;
}
void first(Arc& e) const {
int n = first_node;
while (n != -1 && nodes[n].first_out == -1) {
n = nodes[n].next;
}
e.id = (n == -1) ? -1 : nodes[n].first_out;
}
void next(Arc& e) const {
if (arcs[e.id].next_out != -1) {
e.id = arcs[e.id].next_out;
} else {
int n = nodes[arcs[e.id ^ 1].target].next;
while(n != -1 && nodes[n].first_out == -1) {
n = nodes[n].next;
}
e.id = (n == -1) ? -1 : nodes[n].first_out;
}
}
void first(Edge& e) const {
int n = first_node;
while (n != -1) {
e.id = nodes[n].first_out;
while ((e.id & 1) != 1) {
e.id = arcs[e.id].next_out;
}
if (e.id != -1) {
e.id /= 2;
return;
}
n = nodes[n].next;
}
e.id = -1;
}
void next(Edge& e) const {
int n = arcs[e.id * 2].target;
e.id = arcs[(e.id * 2) | 1].next_out;
while ((e.id & 1) != 1) {
e.id = arcs[e.id].next_out;
}
if (e.id != -1) {
e.id /= 2;
return;
}
n = nodes[n].next;
while (n != -1) {
e.id = nodes[n].first_out;
while ((e.id & 1) != 1) {
e.id = arcs[e.id].next_out;
}
if (e.id != -1) {
e.id /= 2;
return;
}
n = nodes[n].next;
}
e.id = -1;
}
void firstOut(Arc &e, const Node& v) const {
e.id = nodes[v.id].first_out;
}
void nextOut(Arc &e) const {
e.id = arcs[e.id].next_out;
}
void firstIn(Arc &e, const Node& v) const {
e.id = ((nodes[v.id].first_out) ^ 1);
if (e.id == -2) e.id = -1;
}
void nextIn(Arc &e) const {
e.id = ((arcs[e.id ^ 1].next_out) ^ 1);
if (e.id == -2) e.id = -1;
}
void firstInc(Edge &e, bool& d, const Node& v) const {
int a = nodes[v.id].first_out;
if (a != -1 ) {
e.id = a / 2;
d = ((a & 1) == 1);
} else {
e.id = -1;
d = true;
}
}
void nextInc(Edge &e, bool& d) const {
int a = (arcs[(e.id * 2) | (d ? 1 : 0)].next_out);
if (a != -1 ) {
e.id = a / 2;
d = ((a & 1) == 1);
} else {
e.id = -1;
d = true;
}
}
static int id(Node v) { return v.id; }
int id(RedNode v) const { return nodes[v.id].partition_index; }
int id(BlueNode v) const { return nodes[v.id].partition_index; }
static int id(Arc e) { return e.id; }
static int id(Edge e) { return e.id; }
static Node nodeFromId(int id) { return Node(id);}
static Arc arcFromId(int id) { return Arc(id);}
static Edge edgeFromId(int id) { return Edge(id);}
bool valid(Node n) const {
return n.id >= 0 && n.id < static_cast<int>(nodes.size()) &&
nodes[n.id].prev != -2;
}
bool valid(Arc a) const {
return a.id >= 0 && a.id < static_cast<int>(arcs.size()) &&
arcs[a.id].prev_out != -2;
}
bool valid(Edge e) const {
return e.id >= 0 && 2 * e.id < static_cast<int>(arcs.size()) &&
arcs[2 * e.id].prev_out != -2;
}
RedNode addRedNode() {
int n;
if(first_free_red==-1) {
n = nodes.size();
nodes.push_back(NodeT());
nodes[n].partition_index = ++max_red;
nodes[n].red = true;
} else {
n = first_free_red;
first_free_red = nodes[n].next;
}
nodes[n].next = first_node;
if (first_node != -1) nodes[first_node].prev = n;
first_node = n;
nodes[n].prev = -1;
nodes[n].partition_next = first_red;
if (first_red != -1) nodes[first_red].partition_prev = n;
first_red = n;
nodes[n].partition_prev = -1;
nodes[n].first_out = -1;
return RedNode(n);
}
BlueNode addBlueNode() {
int n;
if(first_free_blue==-1) {
n = nodes.size();
nodes.push_back(NodeT());
nodes[n].partition_index = ++max_blue;
nodes[n].red = false;
} else {
n = first_free_blue;
first_free_blue = nodes[n].next;
}
nodes[n].next = first_node;
if (first_node != -1) nodes[first_node].prev = n;
first_node = n;
nodes[n].prev = -1;
nodes[n].partition_next = first_blue;
if (first_blue != -1) nodes[first_blue].partition_prev = n;
first_blue = n;
nodes[n].partition_prev = -1;
nodes[n].first_out = -1;
return BlueNode(n);
}
Edge addEdge(Node u, Node v) {
int n;
if (first_free_arc == -1) {
n = arcs.size();
arcs.push_back(ArcT());
arcs.push_back(ArcT());
} else {
n = first_free_arc;
first_free_arc = arcs[n].next_out;
}
arcs[n].target = u.id;
arcs[n | 1].target = v.id;
arcs[n].next_out = nodes[v.id].first_out;
if (nodes[v.id].first_out != -1) {
arcs[nodes[v.id].first_out].prev_out = n;
}
arcs[n].prev_out = -1;
nodes[v.id].first_out = n;
arcs[n | 1].next_out = nodes[u.id].first_out;
if (nodes[u.id].first_out != -1) {
arcs[nodes[u.id].first_out].prev_out = (n | 1);
}
arcs[n | 1].prev_out = -1;
nodes[u.id].first_out = (n | 1);
return Edge(n / 2);
}
void erase(const Node& node) {
int n = node.id;
if(nodes[n].next != -1) {
nodes[nodes[n].next].prev = nodes[n].prev;
}
if(nodes[n].prev != -1) {
nodes[nodes[n].prev].next = nodes[n].next;
} else {
first_node = nodes[n].next;
}
if (nodes[n].partition_next != -1) {
nodes[nodes[n].partition_next].partition_prev = nodes[n].partition_prev;
}
if (nodes[n].partition_prev != -1) {
nodes[nodes[n].partition_prev].partition_next = nodes[n].partition_next;
} else {
if (nodes[n].red) {
first_red = nodes[n].partition_next;
} else {
first_blue = nodes[n].partition_next;
}
}
if (nodes[n].red) {
nodes[n].next = first_free_red;
first_free_red = n;
} else {
nodes[n].next = first_free_blue;
first_free_blue = n;
}
nodes[n].prev = -2;
}
void erase(const Edge& edge) {
int n = edge.id * 2;
if (arcs[n].next_out != -1) {
arcs[arcs[n].next_out].prev_out = arcs[n].prev_out;
}
if (arcs[n].prev_out != -1) {
arcs[arcs[n].prev_out].next_out = arcs[n].next_out;
} else {
nodes[arcs[n | 1].target].first_out = arcs[n].next_out;
}
if (arcs[n | 1].next_out != -1) {
arcs[arcs[n | 1].next_out].prev_out = arcs[n | 1].prev_out;
}
if (arcs[n | 1].prev_out != -1) {
arcs[arcs[n | 1].prev_out].next_out = arcs[n | 1].next_out;
} else {
nodes[arcs[n].target].first_out = arcs[n | 1].next_out;
}
arcs[n].next_out = first_free_arc;
first_free_arc = n;
arcs[n].prev_out = -2;
arcs[n | 1].prev_out = -2;
}
void clear() {
arcs.clear();
nodes.clear();
first_node = first_free_arc = first_red = first_blue =
max_red = max_blue = first_free_red = first_free_blue = -1;
}
protected:
void changeRed(Edge e, RedNode n) {
if(arcs[(2 * e.id) | 1].next_out != -1) {
arcs[arcs[(2 * e.id) | 1].next_out].prev_out =
arcs[(2 * e.id) | 1].prev_out;
}
if(arcs[(2 * e.id) | 1].prev_out != -1) {
arcs[arcs[(2 * e.id) | 1].prev_out].next_out =
arcs[(2 * e.id) | 1].next_out;
} else {
nodes[arcs[2 * e.id].target].first_out =
arcs[(2 * e.id) | 1].next_out;
}
if (nodes[n.id].first_out != -1) {
arcs[nodes[n.id].first_out].prev_out = ((2 * e.id) | 1);
}
arcs[2 * e.id].target = n.id;
arcs[(2 * e.id) | 1].prev_out = -1;
arcs[(2 * e.id) | 1].next_out = nodes[n.id].first_out;
nodes[n.id].first_out = ((2 * e.id) | 1);
}
void changeBlue(Edge e, BlueNode n) {
if(arcs[2 * e.id].next_out != -1) {
arcs[arcs[2 * e.id].next_out].prev_out = arcs[2 * e.id].prev_out;
}
if(arcs[2 * e.id].prev_out != -1) {
arcs[arcs[2 * e.id].prev_out].next_out =
arcs[2 * e.id].next_out;
} else {
nodes[arcs[(2 * e.id) | 1].target].first_out =
arcs[2 * e.id].next_out;
}
if (nodes[n.id].first_out != -1) {
arcs[nodes[n.id].first_out].prev_out = 2 * e.id;
}
arcs[(2 * e.id) | 1].target = n.id;
arcs[2 * e.id].prev_out = -1;
arcs[2 * e.id].next_out = nodes[n.id].first_out;
nodes[n.id].first_out = 2 * e.id;
}
};
typedef BpGraphExtender<ListBpGraphBase> ExtendedListBpGraphBase;
/// \addtogroup graphs
/// @{
///A general undirected graph structure.
///\ref ListBpGraph is a versatile and fast undirected graph
///implementation based on linked lists that are stored in
///\c std::vector structures.
///
///This type fully conforms to the \ref concepts::BpGraph "BpGraph concept"
///and it also provides several useful additional functionalities.
///Most of its member functions and nested classes are documented
///only in the concept class.
///
///This class provides only linear time counting for nodes, edges and arcs.
///
///\sa concepts::BpGraph
///\sa ListDigraph
class ListBpGraph : public ExtendedListBpGraphBase {
typedef ExtendedListBpGraphBase Parent;
private:
/// BpGraphs are \e not copy constructible. Use BpGraphCopy instead.
ListBpGraph(const ListBpGraph &) :ExtendedListBpGraphBase() {};
/// \brief Assignment of a graph to another one is \e not allowed.
/// Use BpGraphCopy instead.
void operator=(const ListBpGraph &) {}
public:
/// Constructor
/// Constructor.
///
ListBpGraph() {}
typedef Parent::OutArcIt IncEdgeIt;
/// \brief Add a new red node to the graph.
///
/// This function adds a red new node to the graph.
/// \return The new node.
RedNode addRedNode() { return Parent::addRedNode(); }
/// \brief Add a new blue node to the graph.
///
/// This function adds a blue new node to the graph.
/// \return The new node.
BlueNode addBlueNode() { return Parent::addBlueNode(); }
/// \brief Add a new edge to the graph.
///
/// This function adds a new edge to the graph between nodes
/// \c u and \c v with inherent orientation from node \c u to
/// node \c v.
/// \return The new edge.
Edge addEdge(RedNode u, BlueNode v) {
return Parent::addEdge(u, v);
}
Edge addEdge(BlueNode v, RedNode u) {
return Parent::addEdge(u, v);
}
///\brief Erase a node from the graph.
///
/// This function erases the given node along with its incident arcs
/// from the graph.
///
/// \note All iterators referencing the removed node or the incident
/// edges are invalidated, of course.
void erase(Node n) { Parent::erase(n); }
///\brief Erase an edge from the graph.
///
/// This function erases the given edge from the graph.
///
/// \note All iterators referencing the removed edge are invalidated,
/// of course.
void erase(Edge e) { Parent::erase(e); }
/// Node validity check
/// This function gives back \c true if the given node is valid,
/// i.e. it is a real node of the graph.
///
/// \warning A removed node could become valid again if new nodes are
/// added to the graph.
bool valid(Node n) const { return Parent::valid(n); }
/// Edge validity check
/// This function gives back \c true if the given edge is valid,
/// i.e. it is a real edge of the graph.
///
/// \warning A removed edge could become valid again if new edges are
/// added to the graph.
bool valid(Edge e) const { return Parent::valid(e); }
/// Arc validity check
/// This function gives back \c true if the given arc is valid,
/// i.e. it is a real arc of the graph.
///
/// \warning A removed arc could become valid again if new edges are
/// added to the graph.
bool valid(Arc a) const { return Parent::valid(a); }
/// \brief Change the red node of an edge.
///
/// This function changes the red node of the given edge \c e to \c n.
///
///\note \c EdgeIt and \c ArcIt iterators referencing the
///changed edge are invalidated and all other iterators whose
///base node is the changed node are also invalidated.
///
///\warning This functionality cannot be used together with the
///Snapshot feature.
void changeRed(Edge e, RedNode n) {
Parent::changeRed(e, n);
}
/// \brief Change the blue node of an edge.
///
/// This function changes the blue node of the given edge \c e to \c n.
///
///\note \c EdgeIt iterators referencing the changed edge remain
///valid, but \c ArcIt iterators referencing the changed edge and
///all other iterators whose base node is the changed node are also
///invalidated.
///
///\warning This functionality cannot be used together with the
///Snapshot feature.
void changeBlue(Edge e, BlueNode n) {
Parent::changeBlue(e, n);
}
///Clear the graph.
///This function erases all nodes and arcs from the graph.
///
///\note All iterators of the graph are invalidated, of course.
void clear() {
Parent::clear();
}
/// Reserve memory for nodes.
/// Using this function, it is possible to avoid superfluous memory
/// allocation: if you know that the graph you want to build will
/// be large (e.g. it will contain millions of nodes and/or edges),
/// then it is worth reserving space for this amount before starting
/// to build the graph.
/// \sa reserveEdge()
void reserveNode(int n) { nodes.reserve(n); };
/// Reserve memory for edges.
/// Using this function, it is possible to avoid superfluous memory
/// allocation: if you know that the graph you want to build will
/// be large (e.g. it will contain millions of nodes and/or edges),
/// then it is worth reserving space for this amount before starting
/// to build the graph.
/// \sa reserveNode()
void reserveEdge(int m) { arcs.reserve(2 * m); };
/// \brief Class to make a snapshot of the graph and restore
/// it later.
///
/// Class to make a snapshot of the graph and restore it later.
///
/// The newly added nodes and edges can be removed
/// using the restore() function.
///
/// \note After a state is restored, you cannot restore a later state,
/// i.e. you cannot add the removed nodes and edges again using
/// another Snapshot instance.
///
/// \warning Node and edge deletions and other modifications
/// (e.g. changing the end-nodes of edges or contracting nodes)
/// cannot be restored. These events invalidate the snapshot.
/// However, the edges and nodes that were added to the graph after
/// making the current snapshot can be removed without invalidating it.
class Snapshot {
protected:
typedef Parent::NodeNotifier NodeNotifier;
class NodeObserverProxy : public NodeNotifier::ObserverBase {
public:
NodeObserverProxy(Snapshot& _snapshot)
: snapshot(_snapshot) {}
using NodeNotifier::ObserverBase::attach;
using NodeNotifier::ObserverBase::detach;
using NodeNotifier::ObserverBase::attached;
protected:
virtual void add(const Node& node) {
snapshot.addNode(node);
}
virtual void add(const std::vector<Node>& nodes) {
for (int i = nodes.size() - 1; i >= 0; ++i) {
snapshot.addNode(nodes[i]);
}
}
virtual void erase(const Node& node) {
snapshot.eraseNode(node);
}
virtual void erase(const std::vector<Node>& nodes) {
for (int i = 0; i < int(nodes.size()); ++i) {
snapshot.eraseNode(nodes[i]);
}
}
virtual void build() {
Node node;
std::vector<Node> nodes;
for (notifier()->first(node); node != INVALID;
notifier()->next(node)) {
nodes.push_back(node);
}
for (int i = nodes.size() - 1; i >= 0; --i) {
snapshot.addNode(nodes[i]);
}
}
virtual void clear() {
Node node;
for (notifier()->first(node); node != INVALID;
notifier()->next(node)) {
snapshot.eraseNode(node);
}
}
Snapshot& snapshot;
};
class EdgeObserverProxy : public EdgeNotifier::ObserverBase {
public:
EdgeObserverProxy(Snapshot& _snapshot)
: snapshot(_snapshot) {}
using EdgeNotifier::ObserverBase::attach;
using EdgeNotifier::ObserverBase::detach;
using EdgeNotifier::ObserverBase::attached;
protected:
virtual void add(const Edge& edge) {
snapshot.addEdge(edge);
}
virtual void add(const std::vector<Edge>& edges) {
for (int i = edges.size() - 1; i >= 0; ++i) {
snapshot.addEdge(edges[i]);
}
}
virtual void erase(const Edge& edge) {
snapshot.eraseEdge(edge);
}
virtual void erase(const std::vector<Edge>& edges) {
for (int i = 0; i < int(edges.size()); ++i) {
snapshot.eraseEdge(edges[i]);
}
}
virtual void build() {
Edge edge;
std::vector<Edge> edges;
for (notifier()->first(edge); edge != INVALID;
notifier()->next(edge)) {
edges.push_back(edge);
}
for (int i = edges.size() - 1; i >= 0; --i) {
snapshot.addEdge(edges[i]);
}
}
virtual void clear() {
Edge edge;
for (notifier()->first(edge); edge != INVALID;
notifier()->next(edge)) {
snapshot.eraseEdge(edge);
}
}
Snapshot& snapshot;
};
ListBpGraph *graph;
NodeObserverProxy node_observer_proxy;
EdgeObserverProxy edge_observer_proxy;
std::list<Node> added_nodes;
std::list<Edge> added_edges;
void addNode(const Node& node) {
added_nodes.push_front(node);
}
void eraseNode(const Node& node) {
std::list<Node>::iterator it =
std::find(added_nodes.begin(), added_nodes.end(), node);
if (it == added_nodes.end()) {
clear();
edge_observer_proxy.detach();
throw NodeNotifier::ImmediateDetach();
} else {
added_nodes.erase(it);
}
}
void addEdge(const Edge& edge) {
added_edges.push_front(edge);
}
void eraseEdge(const Edge& edge) {
std::list<Edge>::iterator it =
std::find(added_edges.begin(), added_edges.end(), edge);
if (it == added_edges.end()) {
clear();
node_observer_proxy.detach();
throw EdgeNotifier::ImmediateDetach();
} else {
added_edges.erase(it);
}
}
void attach(ListBpGraph &_graph) {
graph = &_graph;
node_observer_proxy.attach(graph->notifier(Node()));
edge_observer_proxy.attach(graph->notifier(Edge()));
}
void detach() {
node_observer_proxy.detach();
edge_observer_proxy.detach();
}
bool attached() const {
return node_observer_proxy.attached();
}
void clear() {
added_nodes.clear();
added_edges.clear();
}
public:
/// \brief Default constructor.
///
/// Default constructor.
/// You have to call save() to actually make a snapshot.
Snapshot()
: graph(0), node_observer_proxy(*this),
edge_observer_proxy(*this) {}
/// \brief Constructor that immediately makes a snapshot.
///
/// This constructor immediately makes a snapshot of the given graph.
Snapshot(ListBpGraph &gr)
: node_observer_proxy(*this),
edge_observer_proxy(*this) {
attach(gr);
}
/// \brief Make a snapshot.
///
/// This function makes a snapshot of the given graph.
/// It can be called more than once. In case of a repeated
/// call, the previous snapshot gets lost.
void save(ListBpGraph &gr) {
if (attached()) {
detach();
clear();
}
attach(gr);
}
/// \brief Undo the changes until the last snapshot.
///
/// This function undos the changes until the last snapshot
/// created by save() or Snapshot(ListBpGraph&).
///
/// \warning This method invalidates the snapshot, i.e. repeated
/// restoring is not supported unless you call save() again.
void restore() {
detach();
for(std::list<Edge>::iterator it = added_edges.begin();
it != added_edges.end(); ++it) {
graph->erase(*it);
}
for(std::list<Node>::iterator it = added_nodes.begin();
it != added_nodes.end(); ++it) {
graph->erase(*it);
}
clear();
}
/// \brief Returns \c true if the snapshot is valid.
///
/// This function returns \c true if the snapshot is valid.
bool valid() const {
return attached();
}
};
};
/// @}
} //namespace lemon
#endif