## What is connected graph give an example?

For example, in Figure 8.9(a), the path { 1 , 3 , 5 } connects vertices 1 and 5. When a path can be found between every pair of distinct vertices, we say that the graph is a connected graph. A graph that is not connected can be decomposed into two or more connected subgraphs, each pair of which has no node in common.

**What does it mean for a graph to be k regular?**

A graph is called regular graph if degree of each vertex is equal. A graph is called K regular if degree of each vertex in the graph is K.

### What is meant by k connected graph?

In graph theory, a connected graph G is said to be k-vertex-connected (or k-connected) if it has more than k vertices and remains connected whenever fewer than k vertices are removed. The vertex-connectivity, or just connectivity, of a graph is the largest k for which the graph is k-vertex-connected.

**How do you prove a graph is k-connected?**

(Expansion Lemma) If G is a k-connected graph, and G’ is obtained from G by adding a new vertex y with at least k neighbors in G, then G’ is k-connected. Proof: Let S be a vertex set that: (a) Is a vertex cut for G’; or (b) has n(G’–S)=1. If (b) is true, then |S∩V(G)| ≥ k; therefore |S| ≥ k+1.

#### Is spanning tree is connected graph explain with example?

A spanning tree is a subset of Graph G, which has all the vertices covered with minimum possible number of edges. Hence, a spanning tree does not have cycles and it cannot be disconnected.. By this definition, we can draw a conclusion that every connected and undirected Graph G has at least one spanning tree.

**Can a complete graph be a regular graph establish your answer by 2 examples?**

Ans: A graph is said to be regular if all the vertices are of same degree. Yes a complete graph is always a regular graph.

## Is K1 a connected graph?

According to Bogdán Zaválniji’s definition of connectivity, if we take any pair of vertices of a graph and there is path connecting them then the graph is connected. So, if we take K1, the only pair of vertices we can take is the single vertex v. But there is no path connecting v and v. So, how K1 is connected.

**How many edges does a connected acyclic graph have?**

It has four vertices and three edges, i.e., for ‘n’ vertices ‘n-1’ edges as mentioned in the definition. Note − Every tree has at least two vertices of degree one.

### Is path a graph?

Paths are often important in their role as subgraphs of other graphs, in which case they are called paths in that graph. A path is a particularly simple example of a tree, and in fact the paths are exactly the trees in which no vertex has degree 3 or more….

Path graph | |
---|---|

Vertices | n |

Edges | n − 1 |

Radius | ⌊n / 2⌋ |

Diameter | n − 1 |

**How do you know if a graph is k-connected?**

An equivalent definition is that a graph with at least two vertices is k -connected if, for every pair of its vertices, it is possible to find k vertex-independent paths connecting these vertices; see Menger’s theorem ( Diestel 2005, p. 55). This definition produces the same answer, n − 1, for the connectivity of the complete graph Kn.

#### What is a k-vertex-connected graph?

A graph is called k-vertex-connected or k-connected if its vertex connectivity is k or greater.

**How to determine the number of connected components of a graph?**

More generally, it is easy to determine computationally whether a graph is connected (for example, by using a disjoint-set data structure ), or to count the number of connected components. A simple algorithm might be written in pseudo-code as follows:

## What is k-edge-connected graph?

A graph is called k-edge-connected if its edge connectivity is k or greater. A graph is said to be maximally connected if its connectivity equals its minimum degree. A graph is said to be maximally edge-connected if its edge-connectivity equals its minimum degree.