unit 5 dm Flashcards
When are two vertices said to be adjacent/neighbours?
one edge between them atleast pic8
What is a null graph
no edges, all isolated vertexes
What is a trivial graph?
no edges and one vertices
What is a graph?
A collection of edges and vertices where the ordered pairs form edges
What does Graph G(V,E) represent?
V is an unempty set of vertices and E is a set of ordered pairs which represent edges
what does the therefore symbol represent (pic1)
null graph, 3 vertices
How is an edge represented?
a line, straight, curvy, long or short
Can the same graph be represented in diff ways? example?
pic2
How can graphs be classified?
finite: finite no. of edges and vertices
infinite: infinite no. of vertices
What are order and set and in which type of graph are the present?
In finite graph
OVSE
Order: no. of vertices
Set: no. of edges
(n,m) graph?
order -> n
size -> m
Graph(V,E) cardinality of V?
Set E cardinality?
|V| = order |E| = size
Null graph with n vertices representation?
(n,0) graph
How are finite graphs classified?
- Directed
direction associated with edge (ordered pair) - Undirected
no direction associated with edge (unordered pair)
What are end vertices?
Vi and Vj are vertices joined by edge ek then edge vertices are Vi, Vj of ek
Symbolically pic3
How are vertices and edges represented?
Vertices: V1, v2 (subscript)
OR
A,B,Cā¦
How are edges and edges represented?
e1, e2, e3..
or
AB, CD, ā¦
Can edges intersect and not form a vertex at intersection point
yes
pic5
even if one vertix diff, denoted as
distinct end verticespic5
self loop?
same vertex as end vertices
pic5
loop?
edges with same end vertices
diff directions
pic5
parallel edges
edges with same end vertices
same direction
pic5
multiple edges
2 or more edges with same end vertix pic 4
simple graph
no loops, no multiple edges
loop free graph
no loops
multigraph
no loops, yes multiple edges