is a comment line.
Comment lines have no semantic meaning and are ignored by bliss.
c A graph representing a Boolean circuit.
where N is the number of vertices and
E is the number of edges in the graph.
In the file format,
the vertices are numbered from 1 to N.
p edge N E
define the colors of the vertices,
v being the number of the vertex and c its color;
c should be a nonnegative integer fitting in the domain of
the 'unsigned int' type in the C++ programming language.
It is not necessary to include a color definition line for each vertex,
the default color for a vertex is 0.
If the color of a vertex is defined more than once,
the last definition applies.
n v c
describe the edges in the graph,
where 1≤v1,v2≤N are the numbers of
the vertices connected by the edge.
Multiple definitions of the same edge are ignored.
e v1 v2
The graph file format itself does not make any distinction between
undirected and directed graphs;
this is done by a tool that uses the file format
(e.g. the command
bliss -directed graphfile).
When the graph file is interpreted as an undirected graph,
a line "
e v1 v2" represents the undirected edge
between the vertices v1 and v2,
and is thus equivalent to the line "
e v2 v1".
For directed graphs,
a line "
e v1 v2" represents the directed edge from
the vertex v1 to the vertex v2.
can be described in the file format as:
c An example graph. p edge 4 5 n 2 1 e 1 2 e 4 1 e 2 3 e 2 4 e 3 4When interpreted as a directed graph, the same description represents the directed graph: