Loading...
Searching...
No Matches
SmartDigraph Class Reference
Data Structures » Graph Structures

## Detailed Description

SmartDigraph is a simple and fast digraph implementation. It is also quite memory efficient but at the price that it does not support node and arc deletion (except for the Snapshot feature).

This type fully conforms to the Digraph concept and it also provides some additional functionalities. 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.

See also
  concepts::Digraph
  SmartGraph

`#include <lemon/smart_graph.h>`

## Classes

class | Snapshot
| Class to make a snapshot of the digraph and to restore it later. More...

## Public Member Functions

| SmartDigraph ()
| Constructor.
Node | addNode ()
| Add a new node to the digraph.
Arc | addArc (Node s, Node t)
| Add a new arc to the digraph.
bool | valid (Node n) const
| Node validity check.
bool | valid (Arc a) const
| Arc validity check.
Node | split (Node n, bool connect=true)
| Split a node.
void | clear ()
| Clear the digraph.
void | reserveNode (int n)
| Reserve memory for nodes.
void | reserveArc (int m)
| Reserve memory for arcs.

## Private Member Functions

| SmartDigraph (const SmartDigraph &)
| Digraphs are not copy constructible. Use DigraphCopy instead.
void | operator= (const SmartDigraph &)
| Assignment of a digraph to another one is not allowed. Use DigraphCopy instead.

## Constructor & Destructor Documentation

## SmartDigraph()

SmartDigraph | ( |  | ) |

inline

Constructor.

## Member Function Documentation

## addNode()

Node addNode | ( |  | ) |

inline

This function adds a new node to the digraph.

Returns
  The new node.

## addArc()

Arc addArc | ( | Node | s,
|  | Node | t )

inline

This function adds a new arc to the digraph with source node `s` and target node `t`.

Returns
  The new arc.

## valid() [1/2]

bool valid | ( | Node | n | ) | const

inline

This function gives back `true` if the given node is valid, i.e. it is a real node of the digraph.

Warning
  A removed node (using Snapshot) could become valid again if new nodes are added to the digraph.

## valid() [2/2]

bool valid | ( | Arc | a | ) | const

inline

This function gives back `true` if the given arc is valid, i.e. it is a real arc of the digraph.

Warning
  A removed arc (using Snapshot) could become valid again if new arcs are added to the graph.

## split()

Node split | ( | Node | n,
|  | bool | connect = true )

inline

This function splits the given node. First, a new node is added to the digraph, then the source of each outgoing arc of node `n` is moved to this new node. If the second parameter `connect` is `true` (this is the default value), then a new arc from node `n` to the newly created node is also added.

Returns
  The newly created node.

Note
  All iterators remain valid.

Warning
  This functionality cannot be used together with the Snapshot feature.

## clear()

void clear | ( |  | ) |

inline

This function erases all nodes and arcs from the digraph.

## reserveNode()

void reserveNode | ( | int | n | ) |

inline

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.

See also
  reserveArc()

## reserveArc()

void reserveArc | ( | int | m | ) |

inline

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.

See also
  reserveNode()