Version 5.0 The LEDA User Manual

AdjIt& ++it performs one step forward in the list of incident edges
of the marked node. If the formerly marked edge was
a leaving edge and there is no successor edge, it is
associated to G.first in edge(n) where G and n are the
associated graph and node. If the formerly marked
edge was an incoming edge and there is no successor
edge, it.eol( ) will be true afterwards. This method
returns a reference to it.
Precondition: it.valid( ) returns true.
AdjIt& −−it performs one step backward in the list of incident
edges of the marked node. If the formerly marked
edge was an incoming edge and there is no predecessor
edge, it is associated to G.last adj edge(n) where
G and n are the associated graph and node. If the
formerly marked edge was a leaving edge and there
is no successor edge, it.eol( ) will be true afterwards.
This method returns a reference to it.
Precondition: it.valid( ) returns true.
4. Implementation
Creation of an iterator and all methods take constant time.
13.8 Face Circulators ( FaceCirc )
1. Definition
a variable fc of class FaceCirc is a face circulator that circulates through the set of edges
of a face as long as the graph is embedded combinatorically correct, i.e. the graph has to
be bidirected and a map (see 11.1).
#include < LEDA/graph/graph iterator.h >
2. Creation
FaceCirc fc;
introduces a variable fc of this class associated with no graph.
FaceCirc fc(const leda :: graph& G);
introduces a variable fc of this class associated with G. The edge
is initialized to nil.
FaceCirc fc(const leda :: graph& G, leda :: edge e);
introduces a variable fc of this class marked with e and associated
with G.
Precondition: e is an edge of G.