In graph theory and computer science, an adjacency list is a collection of unordered lists used to represent a finite graph. Each unordered list within an adjacency list describes the set of neighbors of a particular vertex in the graph.

What is adjacency list example?

An adjacency list represents a graph as an array of linked lists. The index of the array represents a vertex and each element in its linked list represents the other vertices that form an edge with the vertex. For example, we have a graph below.

How do you represent an adjacency list?

In Adjacency List, we use an array of a list to represent the graph. The list size is equal to the number of vertex(n). Adjlist[0] will have all the nodes which are connected to vertex 0. Adjlist[1] will have all the nodes which are connected to vertex 1 and so on.