#include <graph.h>

Inheritance diagram for util::ListGraph< NodeIndexType, ArcIndexType >:

Classes
class	OutgoingArcIterator

class	OutgoingHeadIterator

Public Member Functions
	ListGraph ()

	ListGraph (NodeIndexType num_nodes, ArcIndexType arc_capacity)

void	AddNode (NodeIndexType node)

ArcIndexType	AddArc (NodeIndexType tail, NodeIndexType head)

void	Build ()

void	Build (std::vector< ArcIndexType > *permutation)

ArcIndexType	OutDegree (NodeIndexType node) const

BeginEndWrapper< OutgoingArcIterator >	OutgoingArcs (NodeIndexType node) const

BeginEndWrapper< OutgoingArcIterator >	OutgoingArcsStartingFrom (NodeIndexType node, ArcIndexType from) const

BeginEndWrapper< OutgoingHeadIterator >	operator[] (NodeIndexType node) const

NodeIndexType	Tail (ArcIndexType arc) const
	Returns the tail/head of a valid arc.

NodeIndexType	Head (ArcIndexType arc) const

void	ReserveNodes (NodeIndexType bound) override

void	ReserveArcs (ArcIndexType bound) override

bool	IsArcValid (ArcIndexType arc) const

Public Member Functions inherited from util::BaseGraph< int32_t, int32_t, false >
	BaseGraph ()

	BaseGraph (const BaseGraph &)=default

BaseGraph &	operator= (const BaseGraph &)=default

virtual	~BaseGraph ()=default

int32_t	num_nodes () const

int32_t	size () const

int32_t	num_arcs () const
	Returns the number of valid arcs in the graph.

IntegerRange< NodeIndex >	AllNodes () const
	BaseGraph implementation -------------------------------------------------—.

IntegerRange< ArcIndex >	AllForwardArcs () const

bool	IsNodeValid (int32_t node) const
	Returns true if the given node is a valid node of the graph.

bool	IsArcValid (int32_t arc) const

int32_t	node_capacity () const
	Capacity reserved for future nodes, always >= num_nodes_.

int32_t	arc_capacity () const
	Capacity reserved for future arcs, always >= num_arcs_.

virtual void	ReserveNodes (int32_t bound)

virtual void	ReserveArcs (int32_t bound)

void	Reserve (int32_t node_capacity, int32_t arc_capacity)

void	FreezeCapacities ()

void	GroupForwardArcsByFunctor (const A &a, B *b)

int32_t	max_end_arc_index () const

Additional Inherited Members
Public Types inherited from util::BaseGraph< int32_t, int32_t, false >
typedef int32_t	NodeIndex

typedef int32_t	ArcIndex

Static Public Attributes inherited from util::BaseGraph< int32_t, int32_t, false >
static const int32_t	kNilNode

static const int32_t	kNilArc

Protected Member Functions inherited from util::BaseGraph< int32_t, int32_t, false >
void	ComputeCumulativeSum (std::vector< int32_t > *v)
	Functions commented when defined because they are implementation details.

void	BuildStartAndForwardHead (SVector< int32_t > head, std::vector< int32_t > start, std::vector< int32_t > *permutation)

Protected Attributes inherited from util::BaseGraph< int32_t, int32_t, false >
int32_t	num_nodes_

int32_t	node_capacity_

int32_t	num_arcs_

int32_t	arc_capacity_

bool	const_capacities_

Detailed Description

template<typename NodeIndexType = int32_t, typename ArcIndexType = int32_t>
class util::ListGraph< NodeIndexType, ArcIndexType >

Basic graph implementation without reverse arc. This class also serves as a documentation for the generic graph interface (minus the part related to reverse arcs).

This implementation uses a linked list and compared to StaticGraph:

Is a bit faster to construct (if the arcs are not ordered by tail).
Does not require calling Build().
Has slower outgoing arc iteration.
Uses more memory: ArcIndexType * node_capacity()
- (ArcIndexType + NodeIndexType) * arc_capacity().
Has an efficient Tail() but need an extra NodeIndexType/arc memory for it.
Never changes the initial arc index returned by AddArc().

All graphs should be -compatible, but we haven't tested that.

Definition at line 309 of file graph.h.

Constructor & Destructor Documentation

◆ ListGraph() [1/2]

template<typename NodeIndexType = int32_t, typename ArcIndexType = int32_t>

util::ListGraph< NodeIndexType, ArcIndexType >::ListGraph ( )

inline

Definition at line 319 of file graph.h.

◆ ListGraph() [2/2]

template<typename NodeIndexType = int32_t, typename ArcIndexType = int32_t>

util::ListGraph< NodeIndexType, ArcIndexType >::ListGraph	(	NodeIndexType	num_nodes,
		ArcIndexType	arc_capacity )

inline

Reserve space for the graph at construction and do not allow it to grow beyond that, see FreezeCapacities(). This constructor also makes any nodes in [0, num_nodes) valid.

Definition at line 324 of file graph.h.

Member Function Documentation

◆ AddArc()

template<typename NodeIndexType , typename ArcIndexType >

ArcIndexType util::ListGraph< NodeIndexType, ArcIndexType >::AddArc	(	NodeIndexType	tail,
		NodeIndexType	head )

Adds an arc to the graph and returns its current index which will always be num_arcs() - 1. It will also automatically call AddNode(tail) and AddNode(head). It will fail in DEBUG mode if the capacities are fixed and this cause the graph to grow beyond them.

Note: Self referencing arcs and duplicate arcs are supported.

Definition at line 1176 of file graph.h.

◆ AddNode()

template<typename NodeIndexType , typename ArcIndexType >

void util::ListGraph< NodeIndexType, ArcIndexType >::AddNode ( NodeIndexType node )

If node is not a valid node, sets num_nodes_ to node + 1 so that the given node becomes valid. It will fail in DEBUG mode if the capacities are fixed and the new node is out of range.

Definition at line 1168 of file graph.h.

◆ Build() [1/2]

template<typename NodeIndexType = int32_t, typename ArcIndexType = int32_t>

void util::ListGraph< NodeIndexType, ArcIndexType >::Build ( )

inline

Some graph implementations need to be finalized with Build() before they can be used. After Build() is called, the arc indices (which had been the return values of previous AddArc() calls) may change: the new index of former arc #i will be stored in permutation[i] if #i is smaller than permutation.size() or will be unchanged otherwise. If you don't care about these, just call the simple no-output version Build().

Note: some implementations become immutable after calling Build().

Definition at line 351 of file graph.h.

◆ Build() [2/2]

template<typename NodeIndexType , typename ArcIndexType >

void util::ListGraph< NodeIndexType, ArcIndexType >::Build ( std::vector< ArcIndexType > * permutation )

Definition at line 1206 of file graph.h.

◆ Head()

template<typename NodeIndexType , typename ArcIndexType >

NodeIndexType util::ListGraph< NodeIndexType, ArcIndexType >::Head ( ArcIndexType arc ) const

Definition at line 1153 of file graph.h.

◆ IsArcValid()

template<typename NodeIndexType = int32_t, typename ArcIndexType = int32_t>

bool util::BaseGraph< NodeIndexType, ArcIndexType, HasReverseArcs >::IsArcValid ( ArcIndexType arc ) const

inline

Returns true if the given arc is a valid arc of the graph.

Note: the arc validity range changes for graph with reverse arcs.

Definition at line 230 of file graph.h.

◆ operator[]()

template<typename NodeIndexType , typename ArcIndexType >

BeginEndWrapper< typename ListGraph< NodeIndexType, ArcIndexType >::OutgoingHeadIterator > util::ListGraph< NodeIndexType, ArcIndexType >::operator[] ( NodeIndexType node ) const

This loops over the heads of the OutgoingArcs(node). It is just a more convenient way to achieve this. Moreover this interface is used by some graph algorithms.

Definition at line 1139 of file graph.h.

◆ OutDegree()

template<typename NodeIndexType , typename ArcIndexType >

ArcIndexType util::ListGraph< NodeIndexType, ArcIndexType >::OutDegree ( NodeIndexType node ) const

Graph jargon: the "degree" of a node is its number of arcs. The out-degree is the number of outgoing arcs. The in-degree is the number of incoming arcs, and is only available for some graph implementations, below.

ListGraph<>::OutDegree() works in O(degree).

Definition at line 1160 of file graph.h.

◆ OutgoingArcs()

template<typename NodeIndexType = int32_t, typename ArcIndexType = int32_t>

BeginEndWrapper< OutgoingArcIterator > util::ListGraph< NodeIndexType, ArcIndexType >::OutgoingArcs ( NodeIndexType node ) const

Allows to iterate over the forward arcs that verify Tail(arc) == node. This is meant to be used as: for (const ArcIndex arc : graph.OutgoingArcs(node)) { ... }

◆ OutgoingArcsStartingFrom()

template<typename NodeIndexType = int32_t, typename ArcIndexType = int32_t>

BeginEndWrapper< OutgoingArcIterator > util::ListGraph< NodeIndexType, ArcIndexType >::OutgoingArcsStartingFrom	(	NodeIndexType	node,
		ArcIndexType	from ) const

Advanced usage. Same as OutgoingArcs(), but allows to restart the iteration from an already known outgoing arc of the given node.

◆ ReserveArcs()

template<typename NodeIndexType , typename ArcIndexType >

void util::ListGraph< NodeIndexType, ArcIndexType >::ReserveArcs ( ArcIndexType bound )

override

Definition at line 1197 of file graph.h.

◆ ReserveNodes()

template<typename NodeIndexType , typename ArcIndexType >

void util::ListGraph< NodeIndexType, ArcIndexType >::ReserveNodes ( NodeIndexType bound )

override

Definition at line 1190 of file graph.h.

◆ Tail()

template<typename NodeIndexType , typename ArcIndexType >

NodeIndexType util::ListGraph< NodeIndexType, ArcIndexType >::Tail ( ArcIndexType arc ) const

Returns the tail/head of a valid arc.

Definition at line 1146 of file graph.h.

The documentation for this class was generated from the following file:

ortools/graph/graph.h

Classes

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ ListGraph() [1/2]

◆ ListGraph() [2/2]

Member Function Documentation

◆ AddArc()

◆ AddNode()

◆ Build() [1/2]

◆ Build() [2/2]

◆ Head()

◆ IsArcValid()

◆ operator[]()

◆ OutDegree()

◆ OutgoingArcs()

◆ OutgoingArcsStartingFrom()

◆ ReserveArcs()

◆ ReserveNodes()

◆ Tail()