What is adjacency?

Adjacency refers to the relationship between two or more objects or entities that are located next to each other or have some kind of association. In computer science and mathematics, adjacency commonly refers to the relationship between vertices or nodes in a graph. In a graph, the adjacency represents the connection between two nodes that are directly connected by an edge or a link.

Adjacency can be represented using various methods, including adjacency lists and adjacency matrices. An adjacency list is a data structure that contains a list of nodes and the adjacent nodes to which they are directly linked. An adjacency matrix, on the other hand, is a matrix that shows the connections between nodes in a graph. The matrix contains a 1 if two nodes are connected and a 0 otherwise.

Adjacency is an important concept in various areas of study, such as computer networks, social networks, and geographical analysis. It is used to study the connectivity and relationships between various objects or entities. For instance, in social networks, adjacency can be used to study the connections between individuals and how information spreads among them. Similarly, in computer networks, adjacency is used to study the paths that data takes between different nodes.