A graph is a collection of vertices or nodes that are connected to each other through edges. These edges can be ordered or unordered, which means that the edge can have a direction associated with it or it can be non-directed, which is also known as bidirectional edge. We represent a graph using a set G in relationship with vertices V and edges E as follows:
G = (V, E)
In the preceding diagram, we have five vertices and six edges:
V = {A, B, C, D, E}
E = {AB, AC, AD, BD, BE, CD, DE}
If we consider the previous diagram, the connectivity between A and B can be represented as AB or BA as we have not defined the direction for the connectivity. One of the significant differences between the graph and the tree data structures is that the graph can form a cycle or loop, but a tree data structure cannot. Unlike a tree data structure, we can start from...