Editing Adjacency list (section)

==Operations==
The main operation performed by the adjacency list data structure is to report a list of the neighbors of a given vertex. Using any of the implementations detailed above, this can be performed in constant time per neighbor. In other words, the total time to report all of the neighbors of a vertex ''v'' is proportional to the [[degree (graph theory)|degree]] of ''v''.

It is also possible, but not as efficient, to use adjacency lists to test whether an edge exists or does not exist between two specified vertices.  In an adjacency list in which the neighbors of each vertex are unsorted, testing for the existence of an edge may be performed in time proportional to the minimum degree of the two given vertices, by using a [[sequential search]] through the neighbors of this vertex. If the neighbors are represented as a sorted array, [[binary search]] may be used instead, taking time proportional to the logarithm of the degree.