AdjacencyLists: A Graph as a Collection of Lists

Learn about the representation of graphs by adjacency lists.

Adjacency list representations of graphs take a more vertex-centric approach. There are many possible implementations of adjacency lists. In this section, we present a simple one. At the end of the section, we discuss different possibilities. In an adjacency list representation, the graph G=(V,E)G = (V ,E) is represented as an array, adj, of lists. The list adj[i] contains a list of all the vertices adjacent to vertex i. That is, it contains every index jj such that (i,j)E(i,j)\in E.

Visual demonstration of the adjacency lists

The visual demonstration of the adjacency lists is shown below:

Create a free account to access the full course.

By signing up, you agree to Educative's Terms of Service and Privacy Policy