Topics: Graph Theory - Graph


A graph is said to be connected if we can reach any given vertex from any other one.

That is, a graph is connected if there is an edge between any two vertices. In any other case, we say that is disconnected.

We can also have strongly connected graphs.



A graphic is disconnected if and only if its set of vertices can be divided into 2 or more non-empty disjoint sets, such that there are no edges that start in one of the subsets and end in another one.

We call each of these subsets components.

Two Odd Degrees


If a graph has exactly two vertices of odd degree, then there exists a trajectory that joins them together.

In such a case, the graph is connected.