A structure for representing directed path in a digraph.
GR | The digraph type in which the path is. |
In a sense, the path can be treated as a list of arcs. The lemon path type stores just this list. As a consequence, it cannot enumerate the nodes of the path and the source node of a zero length path is undefined.
This implementation is a back and front insertable and erasable path type. It can be indexed in O(1) time. The front and back insertion and erase is done in O(1) (amortized) time. The implementation uses two vectors for storing the front and back insertions.
#include <lemon/path.h>
Classes | |
class | ArcIt |
LEMON style iterator for path arcs. More... | |
Public Member Functions | |
Path () | |
Default constructor. | |
template<typename CPath > | |
Path (const CPath &cpath) | |
Template copy constructor. | |
template<typename CPath > | |
Path & | operator= (const CPath &cpath) |
Template copy assignment. | |
int | length () const |
Length of the path. | |
bool | empty () const |
Return whether the path is empty. | |
void | clear () |
Reset the path to an empty one. | |
const Arc & | nth (int n) const |
The nth arc. | |
ArcIt | nthIt (int n) const |
Initialize arc iterator to point to the nth arc. | |
const Arc & | front () const |
The first arc of the path. | |
void | addFront (const Arc &arc) |
Add a new arc before the current path. | |
void | eraseFront () |
Erase the first arc of the path. | |
const Arc & | back () const |
The last arc of the path. | |
void | addBack (const Arc &arc) |
Add a new arc behind the current path. | |
void | eraseBack () |
Erase the last arc of the path. |
Path | ( | ) | [inline] |
Default constructor
Path | ( | const CPath< GR > & | cpath | ) | [inline] |
This constuctor initializes the path from any other path type. It simply makes a copy of the given path.
Path& operator= | ( | const CPath< GR > & | cpath | ) | [inline] |
This operator makes a copy of a path of any other type.
const Arc& nth | ( | int | n | ) | const [inline] |
n
is in the [0..length() - 1]
range.